Welcome to HF. No matter which way you go, mobile or base station, most all of your resources (money, effort, etc) should go into your antenna. A rule of thumb is the best antenna is the one with the most aluminum in the sky and as high as you can get it. To help choose a commercial antenna, go to www.eham.net
. In the reviews section, you will get comments from other hams regarding the pros and cons of just about any ham gear you can imagine. Also, I would stay clear of 10 meters. Openings on 10 meters are few and far between due to our current sunspot numbers. 10 meters is a fun band (when it's open) and 10 meter antennas are small and easy to pack. Currently, the workhorse band is 20 meters (17 meters is a close second). But the physical size of 20 meter antennas make them a pain (20 meters = 66 feet!) in the rear. A good mobile antenna brand is HI-Q but at $500 and up they are out of reach for many. You get what you pay for and like I mentioned earlier, most of your system's cost should be in the antenna. Have you considered homebrew? When you build your own antennas you learn quickly what works and what doesn't. I like Dave's idea of not operating while driving but rather set up your temporary station when you get to a good spot. In Moab that might be a high spot on the trail. Good luck.