If you do a lot of exploring any GPS ( I like Garmin ) that can hook up and transfer info to a laptop with map software like MapTech is the way to go. Mapsource is ok but nothing like the USGS maps you can get on disc.
I use an old laptop because the dirt and heat and bouncing is tough on a regular computer.
The democracy will cease to exist when you take away from those who are willing to work and give to those who would not. -Thomas Jefferson