From Professor Shorthair
The DeLorme Earthmate PN-20 has become my main caching GPS unit. I was initially attracted to it by its ability to display satellite imagery and different kind of maps (like topographical maps). It had some strange quirks when it first came out, but most of them have been addressed by firmware upgrades. I have come to appreciate its better features and accept its remaining quirks.

Positive:
1) It is very accurate, even with heavy tree cover. If a cache hider has taken care to get accurate coordinates with a good GPS receiver, sometimes I just walk right up to the cache.

2) It has a “comment” field on the waypoint display page. I have set up GSAK so that the comment box displays the type, size, difficulty and terrain of the cache, and the date of the last find. If I get stuck, a few clicks will take me to an expanded comment screen where I also put the hint.

3) The satellite imagery is cool, even if the resolution is not really good enough to be very useful (see #3 below). The topographical maps have really come in handy while caching in the north Georgia mountains.

Negative:
1) It is slow - slow to draw maps, slow to load waypoints, slow to build a list of nearby waypoints, and so slow to calculate street routes that I don't even try to use that function. It's fine with a direct “arrow” route.

2) You can't group waypoints into different files and folders, as you can with Magellan GPSr units. Garmin users will be used probably not see this as a drawback, but I always liked the waypoint management aspect of my Magellan eXplorist 500.

3) The satellite imagery is not really good enough to be very useful, even if it is cool (see #3 above).

It is also tough and lightweight, with a rubber covering on the back to keep it from sliding on a car dashboard. On a recent cache hunt, my PN-20 went flying through the air when I tripped. It sailed about 20 feet, bounced hard on a granite rock, and was none the worse for wear.