My advice is to keep the water tank full or empty. If it is partially full, it will start to rock and you could loose control. I need to get a baffled tank or a bladder for mine. I almost lost it on the highway before I discovered the problem. Otherwise, it takes the bumps and rolls very well. I have lost a bit of fiberglass from rocks coming up from the tow vehicle, but that's my own stupid fault.
Oh.....and watch the window latches! They will loosen and your windows
out if you haven't secured the latches by glueing or screwing. See other posts on this subject.