I'll post up some pics on this thread soon of my Compact Hunter that I'm building for offroad use. It's not rock crawler worthy but that's not what I was aiming for. The frames on most of the FBRVs are too
light and the clearance too low. Getting over those two hurtles is a big part of it although once you pull the shell off the frame its not too bad to work through the upgrades.
Fiberglass is hard but with hardness comes brittleness so you have stress fracture issues and of course standard off road rock damage. It's a very uncommon platform to start with but if you look around there are a few examples to be found. I personally think it's brilliant. Save the
weight but have a waterproof shell with little set up time. Knowing or at least being willing to learn
fiberglass repair is a bit of a must. I had the unfortunate luck to work in a fiberglass boat shop early in life so I get by but honestly its not rocket science. I knew a lot of real dumb people that did beautiful work. Building this camper has become quite a fun hobby for me and there is lots of great info on this site but you need to look elsewhere for offroad build info. I don't think the trick is in picking the right FGRV, it's more in modifying the one that you find. There are ups and downs to all of them. As an example, my Hunter is a fairly low profile shell because of the pop top. So even with the lift and big
tires the top is still lower than most other FGRVs which keeps it from being top heavy as well as keeps highway wind resistance down. I won't go into the many downsides but I started with it because of the initial price not because it was my dream platform.