I have a home bred gelding, who was a very well schooled dressage horse, on loan to a local program. The program is managed by a very dear friend, and I do have a contract. In fact, the contract states that should she leave the program, I can remove the gelding immediately.
They work very hard to keep him happy. I find that these programs generally do have older horses, as they need experienced, well trained horses for their students. Thus, the good ones know what kind of maintenance they need to do to keep these holder horses going.
I would NOT have loaned him to a number of other programs in this area, including one with International prominence. However, as long as my friend is there, I trust that he is well taken care of. I am also up there every two weeks, so I do lay my hands on him, and check him out.