I've put 425 rounds thru my SW22, all standard velocity stuff that I normally shoot with my Kidd 10/22. I have yet to have a single failure to feed, fire or eject. I've shot Wolf Match Target (1050 fps), SK Standard Plus (1050 fps), CCI Standard Velocity (1070 fps), Eley Club (1085 fps) and Norma TAC-22 (1100 fps). I've got some Federal AutoMatch on order to see how the gun runs with bulk ammo. I'm sure it will run just fine. I suspect the problems people are having are due to manufacturing variability and/or inadequate QC. The slide stop would not engage on the first SW22 I almost bought. Anyway, I absolutely love my SW22, especially the ease of takedown and cleaning. And, I've never had an issue with the takedown screw loosening.