I think for MVCI there is an intermediate state - floating weeks owners who always reserve the same week(s). When we consistently went to Waiohai the week after President's week we would see a lot of the same faces. Some of them were staying 4 weeks or more and considered Waiohai to be their 'winter house'.I've come to realize over the years that owners don't take any better care than exchangers or renters. People are who they are. For us we probably take better care of others things than we do our own. Other than fixed week fixed unit owners, it's just a rental car for owners....
The most info I have is for Disney and while DVC members often think they take better care, I've developed the opinion in that situation that renters take better care of things by a small margin than owners.
The only real pattern I've seen (or heard) at DVC is that the more crowded a villa the more likely there is to be effluvia on the deck or in the hall and more the likely to be noise through the walls or floor. And for whatever reason BCV seems to be worse on those issues than BLT.