None (yet). I'm very careful with mine. I don't play with exposed belt buckles, I don't get near desks, tables, or anywhere else where I could ram one of the "horns" from the body. I invested a lot of cash into it and want to keep it as pristine as possible. It VERY RARELY leaves the house...
...the funny thing about rarely leaving the house is this. Back in April my wife and I were in a bad car accident. I was going to bring my Warmoth to my parents' house for the weekend. I asked her before we left,
Me: Ya think it'll be okay in the gig bag or ya think I should bring the hardshell?
Her: You paid $300 for the case. Keep it in the case, you never know what can happen."
Me: Yeah, you're right, I'll bring the hardshell.
...So, the "you never know what can happen" happened.
The guitar was in the back seat when the crash occurred, and was left overnight in an impound lot in the middle of Baltimore. It was about 40 degrees. The cops would not allow me to remove anything from the car and/or take it to the hospital. I had to pick it up the following morning.
The next morning I picked it up and it wasn't even out of tune by a little bit!

arty07: