I am going on a wheelin' and camping trip to Big Bend this spring and am considering getting a GPS. I have an old (circa 1996), outdated Lowrance that needs to be replaced. I couldn't find my way out of a paper sack with this thing. I want one that has the following capabilities: Topo maps, windshield or dash-mountable, nice-sized screen and readout, compact, and relatively inexpensive. I love the look of the Garmin Streetpilot 660/nuvi (my brother has one that he uses for highway travel), and wish that there was something like that for off-road use. I probably won't use this thing too often, so even an older (read: cheaper) model might suffice. Any thoughts?