The Magellan 315 is a great unit for the price.  I saw that it was also the one Jeraldo Rivera had strapped beside his ships wheel while sailing around the world. I bought it to locate rockhounding sites.

GPS units take some study to properly learn how to use them--and the catalogs that come with them aren't always adequate. Videos are available for many units, and the Coast Guard offers a GPS one day class that is very helpful.  Like anything else, practice, practice, practice!  There is some great software to load before an adventure, topographical applications being most helpful and specific.  A cable that connects both to your computer for uploads and a car cigarette adapter is very helpful as batteries may only run for about 5 hours.  A carrying case to keep the unit clean(er) and protected is a worthwhile final investment.  If you don't want to invest in topographical software, check out the Topozone website; you can put in your coordinates, map it, print it, and have an idea where to start your adventures.  

Do you know about the geocach game where you use a GPS unit to either hide or seek a container that is filled with a log and goodies to find? Great fun!  There is one to check out at:  http://www.geocaching.com/

Happy trails!

Joan