We've used them before with Tuna, Pocky and Tibby and have never had any problems. We don't use them anymore as they are older now and have been trained that humans and furniture are NOT scratching posts. I didn't care so much about the furniture but when Tuna was a kitten he thought it was fun to climb up your legs! I would highly recomment them, it does take a few days for the kitty to get used to them. Once they get used to it they don't even realize that they have them on.