I owned a 2003 Fleetwood Elkhorn 11x from 2009 to 2018. Mine had fiberglass sides, a dry bath, and, of course, was bigger. Overall I was pleased with it.
Mine had an aluminum frame according to the decals. I don't know where it was as the only framing I ever encountered was wood.
The lower edge of the front wall rotted out on mine. I fixed it with some new wood and a big piece of 3" aluminum angle on the exterior.
Also, my side entrance step well had some rot. I fixed that with new wood. The refrigerator didn't want to stay lit but a new circuit board from Dinosaur electronics fixed that.
We used the camper starting with just the wife and I. Then we had 2 kids and used it a lot. We sold it after the third child was born because it just wasn't big enough. Otherwise, I might still be using it. We had it to around 20 states I think over those 9 years.
My Fleetwood only had room for one battery; I always wished I could have added one as we camped with no hook ups quite often.
We camped in it off the truck plenty of times with no trouble.
When I was researching the brand prior to buying mine I found lots of bad reviews about rot but also lots of great reviews. With closer study it seemed like the people complain had fairly new campers and the happy owners had owned them for many years. I decided that meant that if it was going to leak it would happen early on. Since the one I bought was already 6 years old I figured it was probably solid.