|Home||Guest - Not logged in|
Reviews > Navigation and Map Gear > GPS > Delorme Earthmate GPS PN-20 > Test Report by Curt Peterson
DeLorme Earthmate GPS PN-20
Topo USA 6.0 Software
Report Series by Curt Peterson
Initial Report April 2007
Field Report June 2007
Long Term Report August 2007
1)Tester Background and Contact Information
Name: Curt Peterson
Height: 6 ft 3 in (1.91 m)
Weight: 270 lb (122 kg)
Email address: curt<at>boopants<dot>com
Location: North Bend, Washington, USA
I live in the Cascade foothills, just 20 mi (32 km) from the Pacific Crest Trail via trails leading right from my backyard. My outdoor time in Washington is spent dayhiking, backpacking, climbing, and skiing everywhere from the Olympic coast to rainforests to Cascade volcanoes to dry steppe. I played football in college and often evaluate products from a big guy perspective. My typical pack load ranges from 11 - 20 lbs (5 - 9 kg) and usually includes plenty of wet weather gear.
I have owned and used a GPS unit for about 7 years. It is one of the most basic units available. It has served me very well and does a fine job of giving latitude and longitude to find my position on a map. The reception is weak in Washington's dense forests, however, though I rarely HAVE to have a reading – most of my use has been for fun and to feed my outdoor geek curiosity. Where I have found GPS to be a truly amazing tool is in alpine settings with bad weather. It's a long story, but I have no doubt that GPS saved my rear end on Mount Adams about 6 years ago. A whiteout left sky and snow indistinguishable from each other and descending to our tent would have been nearly impossible with map and compass. After wandering for a bit we decided to trust the "go to" feature of the GPS. Believing it was incorrect the entire trek, we still faithfully followed the arrow and stumbled within 10 feet (3 meters) of our tent. That's the day I became a believer in GPS. Truly amazing and a potential nightmare was averted.
I have also always been a bit of a map junkie. Before trips - and even more between trips - I have spent countless hours browsing maps for backpacking and scrambling routes. I use them for dayhikes and backpacking but I have begun to spend more and more time seeking undefined routes off-trail over the past 5 + years. This has placed a high priority on quality, usable maps. The idea of combining a GPS with the computer topographic software is powerful. At the very least it can cut down navigation time, and at best it can open up new routes. With the addition of aerial and satellite images, it offers an unprecedented range of "you are here" visualization.
This Initial Report will focus on the description and features of the GPS PN-20 and the Topo USA 6.0 mapping software. All actual use of these will be reported on in subsequent reports.
The DeLorme GPS PN-20 Deluxe Bundle arrived safe and sound right on the delivery date that DeLorme had e-mailed me with tracking information. The contents were nicely packaged and everything noted on their website as included in the Deluxe Bundle was present except the SD card and card reader. A call to DeLorme customer service got that in the mail quickly and it should arrive any day.
The Topo USA 6.0 on initial inspection is very similar to the previous version, Topo USA 5.0 that was reviewed previously at backpackgeartest.org. It has a more attractive interface and a few new features, but use and navigation around the program is very similar to the previous version. Installation and initial use of the DVDs presented no problems on my computer and was typical in my experience of a quality software installation process. After having used mapping software that involved swapping multiple map CDs, the DVD that contains the entire US on one disk is a welcome improvement. The primary upgrades listed by DeLorme to this version include: Map and Data Updates, a new 3D engine for seamless flyovers, a new toolbar on the top of the screen, more printing options, MapShare functionality, and geocaching support.
The GPS PN-20 is new to DeLorme. It is similar in overall size to many of the backpacker-oriented handheld GPS units on the market. It utilizes buttons on the face of the unit instead of the sides. It's footprint is typical in size, but it's noticeably thick (see picture below). I have big hands and don't find the bulk to be an issue, but this is not a GPS that will slide into a pair of pants unnoticed. In terms of feel, the buttons are raised high above the surface of the GPS and give a definite - and reassuring - click when pressed. They do have a bit of lateral play in them but this doesn't affect their performance so far and I find them very comfortable. The rear of the unit includes a secure battery cover that seals the batteries and SD card in the unit with a rubber gasket. The SD card lies underneath the batteries, so swapping it in and out is not a quick affair. This should only affect users that keep multiple map files on multiple SD cards and those users will have to power off the device to switch maps. The map storage space on even a moderate sized SD card will hold plenty of maps for almost any hike, so this is not really a concern for typical backpacking use.
The "inside" of the GPS PN-20 includes many features that represent the cutting edge of handheld GPS units as of this report:
I'm resisting the urge to report on use and how the GPS has performed in it's first couple of trials. For organization's sake and to hopefully keep this report relatively readable, I will focus the Field Report on the screen navigation, software-to-GPS interaction, reception, and actual functions of the unit.
4) DeLorme Topo USA 6.0 mapping software and GPS PN-20 Test Plan
I will test the software at home on my laptop. I will test the GPS here in the Northwest as spring turns into summer and peak backpacking season. I will use it on valley trails, subalpine mountain backpacking in the Alpine Lakes Wilderness Area, higher cross-country routes in the Alpine Lakes, Central Washington steppe, and hopefully at least one volcano climb. I will also test it on a massive summer road trip from Seattle to Cape Cod and back. We plan to stop in multiple National Parks, Wilderness Areas, and State Parks as we hike, backpack, and car camp our way across the U.S. and back. I just took the GPS PN-20 on a Central Washington trip and have a mid-April trip in northern Utah planned as well as an early May trip in the Alpine lakes. I will be making maps of all trips I take over the testing period.
With the DeLorme Topo USA 6.0 software, I hope to test and report on:
1) Out of the box usability: Can a user familiar with mapping software use it relatively quickly or does it take dozens of hours to learn before the real mapmaking can begin?
2) Zoom: Does the software pan back enough for a big picture, but zoom enough for ridiculous detail. I often will make larger area maps, but also add in extremely zoomed maps of one area that needs as much detail as possible - a couloir I hope to climb, for example.
3) Shaded Relief and 3D Rendering: Are they realistic? Most importantly, do they still serve as a functioning map, or are they just an add-on for effect? To me, a well done shaded relief or 3D map is worthy of being framed and hung on a wall. Does this software produce that kind of quality? How does the new flyover feature work in 6.0?
4) Printing: How easy is it to print maps? Can an accurate "preview" be made? How difficult is it to print multiple maps that connect to make larger maps?
5) How usable are the drawing and labeling tools? This allows me to make my maps truly one of a kind. Will the DeLorme software allow this kind of customization?
6) Accuracy: Almost all map software estimates mileage of drawn or existing trail sections. How accurate is the DeLorme mileage?
7) Updates and Support: If I run into trouble, how responsive is DeLorme? Do they update and patch the software regularly?
8) This software is claimed to easily integrate with GPS units. This is a key feature of this package. In the end, is it worth the trouble and effort to do, or just an option that sounds great, but isn't worth the hassle.
9) Do the maps enhance my outdoor experience? They certainly get me through the weeks between trips and let my mind wander to the wilderness, but do they produce when I'm actually out there? Do they help me find the hidden camps? Do they allow me to scramble to places I normally wouldn't go for fear of what's on the other side of the ridge? Can they get me to water in the middle of nowhere? Ultimately, despite all the computer fun and daydreaming and pretty pictures, this is the test of map software.
10) How do the free downloads work with this software? I used this feature with TOPO USA 5.0 and while very neat, the $50 coupon did not cover very much area. Will the downloads on 6.0 cover the same areas or have they expanded the size of the areas?
With the DeLorme Earthmate GPS PN-20, I hope to test and report on:
1) Out of the box usability: Can a user familiar with GPS units pick up the PN-20 and be using it in minutes or is a manual study session required?
2) Reception: The Northwest is one of the toughest places in the country for GPS use due to dense forests and huge trees. Can the receiver in the PN-20 penetrate the canopy and give a good reading?
3) Usability Outdoors: Is the screen really readable in sunlight? I'm very familiar with transflective displays from my PDA usage and there is a huge variation by manufacturer. Has DeLorme found the right configuration for outdoor use?
4) Battery Life: I could not find an expected battery life during my browse of the DeLorme website. How long will it go? As it will go on multi-day trips, I hope it can last a long time. They do note the use of alkaline, lithium (my preferred), or rechargeable batteries – an appreciated range of options.
5) Integration with Topo USA 6.0? Truly the key to this package – how well does it work? Is the transfer simple? Do all of my notes, icons, and add-ons show up nicely on the GPS rendering of the map?
6) Screen? Is the screen usable for map navigation at that size? The 2.2 inch screen is pretty tight, but I'm used to that as I'm a Palm Treo user and routinely deal with Word and Excel files on a similar sized screen. What I'm not used to, however, is the 220x176 pixel resolution. Is that resolution good enough for map display? I'm used to 320x320 on the Treo – is the lower resolution noticeable? How saturated is the color? Washed out? Vivid?
7) Speed? How fast does the GPS render different images? Does switching from Topo view to Aerial photo view take a couple seconds or minutes?
8) Durability? How durable is the PN-20? It claims to be waterproof – is it? Does it feel solid and tough or do I find myself treating it as a fragile piece of gear?
9) Can I add notes and icons on the GPS unit and send them back to my computer later? This would allow on-the-fly trail journaling – something that would very cool and create a trail history of my outings.
10) Overall – is this the GPS/Software combination that DeLorme outlines – a truly integrated system with top-end capabilities and unprecedented mapping options? Is it something that finds its way into my all-the-time gear kit or is it a techy toy?
5) Initial Report Summary
The pairing of the Topo USA 6.0 software and the GPS PN-20 has the potential to be a backpacker's dream GPS unit. Combining the topographical maps we have known for years with the "you are here" abilities of GPS is truly amazing. Adding in the ability to turn those topos into actual photos - both black and white and color - takes that even further. I hope to determine over the test period if this set can deliver on this promising potential.
This concludes my Initial Report.
Field Report - June 2007
1) Field Report
The Topo USA 6.0 and GPS PN-20 have obviously had quite different testing experiences. The Topo USA 6.0 (and to some extent the GPS PN-20) have been tested in a decidedly non-backcountry setting - at my laptop computer at the kitchen table. I tend to browse new routes for a few minutes almost every day. I work up more detailed routes with map notes and various views about once a week.
The GPS PN-20, however, has seen quite a bit of outdoor use. It got a quick initiation as I took it on a camping road trip from the Northwest to Utah right after it arrived. That trip was 9 days. I loaded the United States basemap on the GPS and used it to track almost the entire route while we were driving in the car. Not trail use, but a great way to learn the functions and test for accuracy. A couple interesting things were learned from this. First, the speedometer on my car is apparently perfectly accurate. The "Speed" on the GPS matched the vehicle at all times and updated frequently enough to track even small fluctuations in rate. The other thing I learned is that the GPS does not necessarily pick up time difference as I crossed time zones. I checked a few different settings to see if there was a "manual" and "auto" time setting, but couldn't find one. I'll see if this is something I have yet to discover or if the GPS just doesn't change with the location during Long Term Testing.
In real trail use, the GPS PN-20 has seen just about everything except very cold weather. I did use it once just a bit below freezing, but most use has been in temperatures ranging from the mid 40s F to the mid 70s F (7-24 C). It's been in bright sun and heavy rain. The rain so far has had absolutely no effect on the unit. It has been on about 4 dayhikes ranging from local Cascade foothill trails to trails along the Snake River in Idaho and Oregon. It also was used near the Potholes Reservoir in Central Washington for a 2 day/1 night trip and near Easton, Washington near Snoqualmie Pass in the Cascades for another 2 day/1 night trip. I estimate that I have used it for some sort of navigation on about 12 days total at this point.
DeLorme Topo USA 6.0 software
The Topo USA 6.0 software has not difficult for me to use. It's not ridiculously simple though, and there are a couple of things that take some getting used to, but overall it's extremely capable and feature-rich and that involves a certain level of complexity. I believe I have a clear advantage in using the Topo USA 6.0 as I have been using Topo USA 5.0 for quite awhile. Learning how the tools work and what is possible takes a lot of time and tinkering. Even with the experience, I've found some things that just aren't intuitive to me or take re-learning nearly every time. Most of the common features, however, work fantastically well. In particular, scrolling and zooming work very well and it's really fun to explore areas quickly and in great detail. The base map is all in DeLorme's digital topo data series. If more maps are wanted, DeLorme offers Aerial Data Packs (ADPs) which include aerial photos, color aerial photos, color satellite images, and USGS quads. These cost money, but Topo USA 6.0 ships with a coupon for $100 US worth of downloads.
Incredibly, all images - including the photos and USGS quads - can be rendered in 3D. The areas I checked that I've been to for real-world reference are a very accurate representation of reality. Here are 4 sample pictures - in 2D and 3D - of the exact same area in the various options for viewing. I picked these photos because the ADP that I downloaded for this area borders on a section that I did not purchase, showing how the various maps integrate with the Topo USA 6.0 base map.
Tons of options make these views even more variable - shading can be turned on and off, elevation can be exaggerated, layers of notes and routes can displayed or not - it really can be overwhelming how many options there are. Add to this the ability to pan around as if in a helicopter - in 3D - and it's a pretty neat experience.
Trail update accuracy is mixed. My local dayhike trail just outside my back door did not show up in Topo USA 5.0. It is one of the most popular close-to-metro-Seattle hikes (Rattlesnake Ledge for you locals) and I was surprised it didn't show up on the software. Curiously, it's not in this new Topo USA 6.0 version either. Perhaps the strangest part is that the Rattlesnake Mountain Trail - which my understanding is much newer than the Ledge Trail - is on the map, as are many of the old logging roads in the Cedar River Watershed, which is closed to all public access. I'm not naive enough to think that any software would be 100% accurate and up to date with the constantly changing trail system, but this is one example that I have kept an eye out for that I found interesting results for. Almost every other trail I've checked has been accurate.
So far, DeLorme has had pretty incredible support, providing multiple updates and downloads. There have been nearly constant individual state updates (15 state updates after checking today - although none for Washington) plus some important updates for everyone, including Service Pack 2 - targeted specifically at PN-20 users for Topo USA 6.0 - and a Firmware Update with a bunch of useful small changes for the GPS PN-20. Taking advantage of these has been a mixed bag so far. The Topo USA 6.0 was a simple upgrade with immediately noticeable changes. The GPS PN-20 has been a different story, which I'll discuss below in the GPS section.
DeLorme Earthmate GPS PN-20
As a unit completely separate from the Topo USA 6.0 software, the GPS PN-20 is an excellent device that stands on its own very well. When I first opened it, the GPS was instantly usable without any directions or how-to walkthroughs. I learned plenty of little tricks and discovered new functions by reading the manual carefully, but the basic GPS functions are easy to figure out and turning it on and getting the basic setup done is very straightforward. This is the third GPS unit that I've used extensively, and it is by far the simplest interface.
The operating system and graphical user interface is exceptional - easily the top feature of the entire package - Topo USA 6.0 or the GPS PN-20. Perhaps the coolest features of this best aspect are the incredible user customization options. It's possible to make the entire user experience almost exactly as I could want it. Everything from the number and types of the "pages" to scroll through to the exact content on each of those pages is possible to customize. Only want to see the elevation and current position? It's possible. Want to see the sunrise, sunset, trip odometer, and average speed? It's possible. Even the color scheme of the entire interface and the sounds that the unit makes when buttons are pushed is optional. I've always been one that likes things "just so", so this level of individualization is fantastic. I have my computer a certain way, my phone/PDA a certain way, and being able to make the GPS just how I want it is great. I don't like a lot of clutter and when I'm on the trail I just want a couple of pieces of information like elevation, coordinates, and time. I can make this happen with the GPS PN-20. As a bit of an electronic gadget geek, I am very impressed with the thought that went into the user-friendliness and real world usability of this unit.
The actual on-trail experience is just as impressive as the customizability. I have been able to get a locked signal quickly everywhere I have tried, including the trails near my home that are under very tall Douglas Fir trees and up against the base of a mountain. I was never able to get a signal on my previous GPS at this location. Not only was I able to get a signal, but it stayed locked for a 2 mile (3.2 km) walk through dense woods. Once it has a signal, it's tenacious in its maintenance. Scrolling around maps is smooth and controlled. It does seem a bit slow at times, but it moves quickly enough. Zooming in and out is equally smooth. The new pages don't take long to refresh - certainly much faster than I expected. As far as the core functions of a mapping GPS - signal, map movement, and signal maintenance - the GPS PN-20 shines. I am confident saying that this is the strongest aspect of this test so far. The GPS function is top notch.
The screen is very usable. My understanding of the way these screens are made is that they can be tuned for optimal indoor use or optimal outdoor use. This is the same for most PDAs, cell phones, and other flat small screens like this. Deciding how to tune this range is always a balance manufacturers must decide. I think that DeLorme got it right, leaning to the benefit of outdoor use. Screen brightness is adjustable, so some tweaking of this aspect is possible. The screen is not as sharp and bright as a high-quality smartphone, but it's certainly good enough for what it's supposed to do. I have had no troubles reading map features or seeing what I'm doing on the GPS. Would I like a bigger, higher resolution screen? Absolutely. But bigger, better screens are more expensive and eat battery life, so compromises are inevitable. This is a very usable screen that does well and shows colors vividly and features sharply.
The battery life so far has been great. There are three options: AA alkalines, AA lithiums, or the rechargeable lithium. All last a very long time - even with being constantly on. With intermittent use for just locating a position, I have no doubts I could go at least a week with this GPS. One interesting thing is that the battery indicator is calibrated to the different batteries. This is buried in settings and needs to be changed by the user. Unbeknownst to me I had the battery setting for AA alkalines but was using the rechargeable lithium battery. It showed the battery charge at nearly 100% for over a day of near constant use before it plummeted in a very short time. Changing the setting to the correct battery shows a much more steady decline that seems to follow the real drain of the battery.
Durability is mostly good so far. The unit itself inspires a lot of confidence in regards to being rugged. It's got a rubberized back grip and the plastic feels much more solid and sturdy than most plastic electronic devices these days. Squeezing it and twisting it has no effect - it's put together very sturdily. The rechargeable lithium battery fits very snugly, and pulling on the black fabric tab used to lift the battery out of its compartment caused it to come loose after about a dozen uses. The only other thing that I've come to notice as a potential concern is what appears to be one row of pixels across the screen that is somehow damaged. It's not a black line, but it's not consistent with the rest of the screen. I'll see how this progresses and report in the Long Term Report on whether or not it turns into something more serious.
The accessories that came with the GPS PN-20 are excellent. The card reader, various car and plug adapters, battery charger, and screen protectors all work perfectly and add a lot to the overall ease of use. In fact, at this point, the card reader and SD card are what have made the GPS usable with maps.
My only complaint so far with the Topo USA 6.0 and GPS PN-20 setup is the interaction between the two. I've had both hardware and software problems. My main concern is the hardware. I have a cable that either has a short in it or not all of the pins are working on the cable or the GPS itself, but I have had a lot of trouble getting the GPS and the Topo USA programs to interact. Unfortunately, even though maps can be transferred via the SD card to make it still functional, at least one connection needs to be made to allow this to happen. That initial connection took me hours to accomplish. I spent a long time reading the DeLorme forums (very helpful!) and help sections. I did troubleshooting on my USB ports even though nothing seemed wrong with them. Ultimately, a tight squeeze of the cable in the GPS and just the right wiggle and I had a connection long enough to get the initial connection completed. Since then, I have used the SD card transfer system exclusively. It's quick and reliable and I've had zero problems with that. In fact, for my last trip I had made a number of fishing-specific notes on the Topo USA 6.0 software and at the last minute remembered I hadn't transferred them to the GPS. In a hurry I started up the Topo USA software, popped in the SD card in the reader, and with just a few clicks sent the maps with custom notes to the card. I stuck the card back in the GPS and everything was there, ready for a trip to the mountains for a weekend of fishing. Unfortunately, having a good GPS with maps doesn't have a direct correlation to fishing success! I didn't think much about the cord again until the Firmware Upgrade became available. It appears to have some significant improvements, but I can't get a good connection to load it. So far I've attempted it for a couple of hours total. I'll try again during long term testing and if I'm unable to get a good connection soon I will contact DeLorme for a new cable, hoping it's that and not the GPS itself. This is the only way to update the GPS, so it's pretty important to me that it gets worked out.
2) Field Report Summary
Overall, I'm pretty happy with both the Topo USA 6.0 software and the PN-20 GPS. In a perfect world the GPS would be thinner, have a bigger screen, and the software would integrate seamlessly with online maps like Google's and Yahoo!'s. As a first generation high tech device, a few hiccups are to be expected. I wish my cable attached securely and the transfer between GPS and PC was easier. For 2007, however, this is about as cool a backpacking setup as I've used. Topo maps - and satellite images - on a GPS with the ability to zoom, pan, label, and more? What's not to be happy about?!
Individually, the two parts of this test are pretty amazing. The Topo USA 6.0 has a lot of capabilities - more than can be realistically used without endless hours of tinkering and tweaking. The GPS PN-20 is a very good GPS as far as getting and holding a signal and seeing where one is on a map and moving that map around. For me, the only issues arise when the two main components try to talk to each other. Admittedly, this is a big deal since that's one of the most important features of the setup. At this point I believe it's a solvable issue and it will be a core focus of the remaining test period.
This concludes my Field Report.
Long Term Report
1) Long Term Report
The Topo USA 6.0 and GPS PN-20 have had a workout in the last two months. I am writing this report during week four of a five week trip from Seattle, Washington to Cape Cod, Massachusetts and back. Much of this trip was planned and mapped using the Topo USA 6.0 software and maps have been downloaded onto the GPS PN-20 that cover a route literally from one side of the United States to the other. Most of the use of the Topo USA 6.0 software was pre-trip, although I have used it a few times during the trip - primarily to transfer files back and forth to the GPS. The PN-20, though, has been used almost daily. In sheer number of hours used most has been while traveling in the car (it takes a long time to drive across the country and back after all) but it has been used outdoors all over the place. In particular it pulled outdoor duty near Bozeman, Montana, the Chippewa National Forest in northern Minnesota, the Upper Peninsula of Michigan, the boonies of Ontario, Canada above Lake Huron, in the Catskills of New York, and around the National Seashore on Cape Cod. It has been used a bit less on the return trip but saw use in southern Minnesota, in Badlands National Park in South Dakota, and we still have a few days left in Wyoming and Montana where it will likely be put to use as well.
The weather has been decidedly hot. We were in temperatures over 100 F (38 C) for almost the entire first week. We spent 3 weeks in the Midwest and eastern U.S. in temperatures in the high 80s F and 90s F (31 C to 35 C) with very high humidity, and the return to the West has started off extremely hot as well - it's 110 F (43 C) as I write this in Badlands National Park. We've been hit with a couple of serious thunderstorms, but so far none of them have occurred while using the PN-20.
DeLorme Topo USA 6.0 software
The Topo USA 6.0 software has continued to work well for me. I still get hung up on some tasks that I feel I should have memorized by now, but I always find out how to do what I want eventually. It does seem that the program loads a bit slower than it used to. I'm not sure if this is due to more saved maps and routes and icons or is due to a general computer slowdown, but it is noticeable - particularly at startup. Scrolling is affected at times as well, but again, I can't be sure it's the program or my computer.
There have been a number of new downloads for the Topo USA 6.0 software for states - although still none for Washington. There have not been any further general software updates since the Service Pack 2 that I continue to use.
The downloadable Aerial Data Packets (ADPs) work pretty much as described by DeLorme. After going through the selection and checkout process, instead of being able to view only DeLorme's topos I have the option to see USGS Quads, Color Aerial Imagery, Aerial Imagery, or Satellite Imagery. My only complaint with the downloads is the cost. The USGS, aerial, and satellite pictures are all available for free with a little hunting on the web. Paying for them to integrate into DeLorme's software causes me a little head scratching. In my opinion including the multiple views and maps would really set the Topo 6.0 software apart and make it a fantastic value for backpackers.
DeLorme Earthmate GPS PN-20
My cable problems persisted throughout most of the test period. After a bunch of wiggling, jiggling, reading the DeLorme forums, and getting advice from fellow BGT testers, I was finally able to get a reliable connection between my PC and the PN-20. The primary USB cable no longer works at all for me. The combination that is making transfers possible is a USB to mini-USB cable plugged into an adapter that accepts the mini-USB and connects to the PN-20.
Once I was finally able to reliably connect my PC to the PN-20 I was able to re-flash the GPS ROM with a firmware update. It went well and I didn't encounter any problems. There are over 20 changes in the free update. Some of the more notable changes from DeLorme's website include:
Info Field Updates:
Except for the primary connection cable the accessories are excellent. I've been on the road for 4 1/2 weeks and have been able to find a way to keep powered up in any situation. Home, car, power block, and even a hand crank charger have worked. I used lithium AA batteries for the first half of testing and have used the rechargeable lithium-ion battery since. The lithium AAs seemed to definitely last longer, but the rechargeables last plenty long in my experience and have the obvious advantage in cost since they aren't trash after they expire. For any 1 to 3 day trip I'd feel comfortable with just the lithium-ion rechargables. On a longer trip or one where I expected heavy GPS usage I'd probably start out with the rechargeables and carry a pair of disposable lithiums as a backup. Combined this would meet my needs for a week or more quite easily. I tend not to leave it on for route tracking. My typical use involves a quick location check, possibly a sunset time verification, and an elevation estimate. Most other features are used in camp playing. I do occasionally mark a spot on a map with a note on it if I want to remember something about a particular location (type of fish, flies that worked, etc.) but this is a pretty quick process and then I usually turn it off again.
2) Long Term Report Summary
Overall, the DeLorme Topo USA software and the GPS PN-20 have been great to test. There are a bunch of things I really like about these products - and just a few things I think would make them better:
Read more reviews of Delorme gear
Read more gear reviews by Curt Peterson
Reviews > Navigation and Map Gear > GPS > Delorme Earthmate GPS PN-20 > Test Report by Curt Peterson
If you are an avid backpacker, we are always looking for enthusiastic, quality reviewers. Apply here to be a gear tester.