I always liked these things. Don't know how they were offroad, but Revcon had a good rep for quality...
Off-roading will need to be chosen carefully. This thing is 35 feet long, if I recall correctly.
Revcon motorhomes were some of the best of the free-for-all period in the 70's before designs and equipment suppliers became standardized. They were built like an airplane fuselage of the time, using aluminum and rivets. They were front-wheel drive with Torando 455 cubic inch V-8 engines, like the GMC motorhomes, and this allowed a low floor and very low center of gravity. I had one for a while, and have kept a copy of a magazine article describing Bob Bondurant running laps in one around Sears Point.
But by the early eighties, the aluminum models at 26 feet long had been replaced with much longer, much more standard-style, fiberglass models. And if my memory is correct, the '90s Trailblazer had almost none of the original Revcon ownership and DNA left in it.
Great rig, though (except the 6 city/8 hwy mpg is a bit déclassé these days) and conceptually a bit like a giant EarthRoamer XV-LT with much lower pricing. FWIW, there is a web listing--don't know if it really is for sale any more--of one that includes many useful pictures . . . you know, in case you're getting serious.
http://revcon4x4.com/listings/trailblazer/