I use my ladder often. There are a couple of issues I have noticed. My ladder is screwed to the back wall of my trailer; each support flange has two screws, one on each side of the ladder tube. As a point of information to judge how much stress I put on the ladder when I use it, I weigh about 185 pounds. In spite of the issues with the ladder, I'm glad my trailer came equipped with one.
These are the problems I have had:
1) The end of each rung has a plastic formed bushing at each end. Two of those bushings have broken.
2) The end of each rung is fastened into the ladder tube with a screw; one of those screws broke.
3) The flanges that attach to the back wall have deformed slightly and pulled away from the wall. Caulking at the flanges cracks due to the slight deformation and stress; I have put Eternabond over the flanges which so far has worked well.
There's lots of advice and information in forums... sometimes it is correct. For example, all of my posts are made by a political appointee who got the job as a reward for contributions to my diesel bill.
2011 Jayco 28.5RLS; 2008 Chevy Duramax; Pullrite Superglide Hitch