My Mosquito lasted a few thousand rounds then would not fire anymore. The slide had cracked on the left hand side from the back about 1" through the safety relief cut. I got it replaced under warranty as it is a known defect. Took 13 months of sitting at the warranty depot. With the new slide it runs like brand new. That is to say "BANG, click, rack, BANG, click, rack, BANG, click, rack click, click, f**k, click rack, click, rack, f**k, BANG, click, rack, click, rack, reload, click, click, click, rack, BANG BANG, click, rack, f**k. Great for teaching immediate action drills. Should have bought a Classic P226 .22, they run like a top.