I don't know that I have much of a story as far as what happened while pets were at sitters, but I can offer this much:
Our house burned in February. Prior to the house burning, we had 3 dogs, 2 cats, and a fish. One of the dogs died (not in the housefire), but we were still left homeless with 2 dogs, 2 cats, and a fish.
We sent one of the dogs to some of my husbands family where he is staying until we get back into the house. He is doing absolutely wonderful.
The other dog, we didn't have a place for, and she ended up going to stay with Teffie from here on YT. I did not know Teffie prior to that, but she took extraordinary care of my little Pixie. Pixie is back with us now.
We put the cats in the safe haven program at the humane society, but they had both cats shoved in 1 cage... and we decided that was inhumane to leave them like that for any length of time. We released the older one for adoption, not really believing she'd be adopted since she was older - and she went to her new home within a week. The other cat we tried to bring home and keep, but it didn't work out, and she's also in a new home and very happy.
Overall, I've had very good luck with leaving my babies in various places with all different kinds of people