191 is o.k. for RVs...many do it. Just a heads up you'll have a steep downhill into Vernal. Get in low gear at the top before you head down and you'll be just fine.
We stayed at Fireman's national forest campground at Flaming Gorge - very nice huge sites; dry camping. It's on the rim overlooking Flaming Gorge reservoir.
We've also used Steinaker State Park at the bottom of the hill of 191.
Dinosaur Nat'l Mon. also has a nice campground.
The town of Vernal isn't much.
Sounds like you'll be having a nice trip!
