I would agree with Al in regards to the bowman ring. On the engine that I just repaired there was very little staining below the ring=very little blowby on the stock ring. I see no reason to replace it with an aftermarket ring.

9K to much? Possibly, but I use this one for 3D type of flying. I'm using a 17X6 Xoar now and we'll see how that does.

No trouble, just part of the game. Unusual failure? Time will tell on that subject. Right now it seems to be identified as the weakest link.