I've noticed a couple, very small indentations on my TAF's chair scoop Cliffy. Only very recently have I also noticed the ball going into that scoop a bit more easily than before. That's what prompted me to look closely at the Cliffy. Granted, the area underneath those "dents" is open air so it's not damaging the wood at all, but it still shows me that they're susceptible to some damage. I'd say that my TAF has had about 1,000 plays on it since I installed the Cliffy. Thankfully, it's a common one that most people carry all the time. I think I'll just pick up a spare one at PAGG, just to be safe.