Sorry, I don't think ware will be an issue. I might have close to a couple thousand rounds on one sample and it is completely fine with no signs past rub marks which the factory get as well. Also if it ever does ware out just send it back and we will replace it with a new one. I really don't think that will be an issue though. My thought is if someone fire enough rounds on one to ware it out I'd love to see the end result and they deserve a new one!
Yes, Some will do this. The finish blistered slightly on the back in the center of the piston. You will find that it will not spread