I received my M&P back from S&W and test fired it last weekend. Smith & Wesson replaced the slide, barrel and recoil spring. I was so happy to get it back! I went out with 100 rounds of Blazer Brass. The first 50 rounds went off without a hitch. The second box had 4 failures to go into battery. The rounds were stuck half way into the chamber. Each time a pull and push chambered the rounds. Right now I am keeping my fingers crossed that it is just a break in issue. When I cleaned it, the problem seemed to disappear. I will take it out tomorrow and try it again. Accuracy seems to be better, though after shooting a heavy, steady 1911 for quite a while I really feel like I must stay on top of my game to shoot the M&P accurately. It is definitely not as forgiving as my 1911, probably due to the lighter weight. The lighter weight sure does makes it easier to carry than that old battleship 1911! Hopefully, it will sort itself out.