I just had a ZDZ80 piston fail this weekend! Not due to a wrist pin clip though. The piston just lost a piece from the ring to the top including a chunk of the ring. The engine kept running long enough to get lined up with the runway then quit.

Although there is no warranty on mine, only the piston, ring, and cylinder casting were ruined. The pieces just exited the exhaust without getting into the case. I'm gonna repair it and fly it again, but the parts won't be available for several weeks!

I don't have any reservations about ZDZ engines though. Engine parts do break sometimes (you get used to it when you drive Chevy's)

Ben