There is a Lance owners forum which is open to the general public. Check it out and also google for problems and different camper brands. Appreciate also that materials have improved somewhat in past 10 years though camper manufacturers are no where near as good as their brochures would lead you to believe.
Only problem I would be concerned about is water coming into the roof or the side walls as this is expensive to repair and likely to appear after the camper is out of its very short 1-year warranty period. The fiberglass ones which I would have thought to be the least likely to have problems have turned out to have more problems than most.
I know that before I bought another camper I would research this area more diligently and spend time of the roof of any campers I was looking at. At least with Lance the approach is to cut a hole in the roof, insert the vent or AC or skylight, or ceiling fan, and then caulk it like crazy. Downside to this approach is the need to regularly go up on the roof and clean or strip old caulk and apply a new layer and the hundreds of feet of caulking takes time to maintain properly.
I would also look for access to wiring and components. With my Lance the converter and charger unit is buried in the cabinetry and there is no structured access for the wiring where the meters are located, a stereo is installed, and the TV is mounted. It is a veritable rat's nest that looks like it was designed by monkeys.
Campers also differ in terms of holding tank capacity and the degree to which these tanks are protected from freezing. This may not seem important but it will affect your use of the camper and the ability to boondock and the length of your season of use. We experienced the fresh water line freezing after two days of 24 degree temperatures during an early October September trip to Yellowstone, so not like being there in the "winter" but still caused problems.