I do Nevada a lot and I use an ATV. Exploring mines, ghost towns, blips on maps, out of the way places, not roads, sand, dunes, wide open spaces. If you're out there to go fast and climb boulders the SxS is probably the way to go. But the SxS just can't go where ATVs can. SxSs have their place, but most of them are pretty big. I'm not a fan of belts either, but my ATV is belt driven, and it has given me no problems, and I've crawled up some pretty rocky creekbeds and know I've heated it up. If you're set on a SxS, the Honda Pioneer is shaft drive and still somewhat narrow. It has been the most appealing to me. But I wouldn't shy away from a used Yamaha Rhino or Wolverine just because of a belt.
If I was in the market for a SxS, I really like the specs of the Yamaha YXZ- shifter tranny and a rear diff, but I have no personal experience with it. It's also hard to stomach $20k for something costing more than my daily driver. But hey- Muhrica? Good luck.