The Garmin 12XL GPS is a 5 star product. It is very rugged and has been to the summit of Mount Whitney, Claifornia twice, as well as used on an unsuccessful summit bid in January 2001. As a hand held device, it is very hardy, small, and lasts for about 24 hours on the AA batteries. While it does not have topographic mapping software, that is good, as it forces you to use it with a map and compass, which whould be taken on any trip in case the GPS "dies" for what ever reason. With the external antenna feature of th 12XL, you can carry the unit under your coat and have the antenna out to receive signals. This is important because my experiences with liquid crystal display in the 8F weather on Whitney, proved the display was "out of action" until properly warmed up in very cold weather. And without a display, the GPS is just another "rock."