I bought one a few years back. Zero function issues with store bought 115 and 124 grain FMJ Winchester as well as the 147 grain Winchester hollow points. Also the 115 grain Federal FMJ ammo worked well in it. I've tried 115 grain and 124 grain hollow points (my reloads) and had zero issues with it.
My issues with the pistol were poor groups. I added an Apex trigger kit (awesome trigger pull that did not improve groups). Then I added an Apex file to fit barrel and that did help groups. So far the only good groups I"ve shot with it use the Winchester 124 grain FMJ NATO ammo (also shoots good groups in my Shield Plus 9MM). I barely started working on a 9MM 124 grain hollow point load before I got sidetracked by something else. I have bullets and two or three new powders to try. I like that pistol, I just want it to shoot better groups (like the Shield/Shield Plus pistols). I'm hoping at least one of the new powders I've got to try will get me there with the 124 grain hollow points.
Honestly, I sometimes see the same model in .40 S&W and consider (briefly) getting one of those. Since Apex doesn't make .40 S&W barrels I've held off on it. Really, the M&P pistols just fit my hand and feel so good it's a shame they don't shoot better.
Good luck with yours, if you get one.
Added incentive: