Its a great gun, better than a Glock IMO (and I own a Glock now).
I've owned both the M&P 9mm and 40 in full size before and they were excellent pistols. I've never understood how people complained about its factory trigger. It has no creep like XD's and no annoying scissor-type trigger safety like Glocks. 3 Interchangable backstraps and its fully ambidextrous even if you get the thumb safety. It also has a better slide finish than XD's and Glocks.
And it comes with Smith and Wesson's excellent lifetime warranty. Buy with confidence.