My parents, and several others that I have heard of, have had them fall off of the ladder racks usually with damage to the ladder, but the hitch mounted racks seem to do better. Just remember that the bouncing (as stated earlier) is huge, and the bike racks that have some kind of locking straps for the bikes are usually plastic, so good, extra strapping is a must on the back of any RV. My rack is also strapped from side to side to limit wobbling as there seems to be a lot of play in most of these hitch mounted racks.