I've used S&W 2nd and 3rd generation semi auto's, for the past 20 years.
I've yet to have a bad one. They are well built (some models in 45, could be described as tank like) reliable, accurate, and I find some of the models, such as the 4506, 4516, and 3913 aesthetically pleasing too.
Because they are bad mouthed so often on the internet (IMHO by people who probably haven't shot one, much less owned one) they are very under valued, and most models can be found for cheap. Police trade in 3rd generation S&W metal framed pistols, are a best buy, IMHO of course. Where else can you find a compact single stack 45, with ambi safety, and three mags, NS, for under $400 ?
Some models are DAO, the 4586, 4553, 3953, and 4053 come to mind. There are also many TDA models available in all calibers.
Two of my favorite S&W metal framed pistols are the 3913, a compact, TDA single stack, aluminum framed 9mm, and the 4516-3, a compact TDA single stack 45, of all SS construction. Both of these pistols have been reliable and accurate for me. I stake my life on the 3913 daily, thats about as much praise as I can give any handgun.
I'm not a S&W fanboy, and have no use for the M&P pistol. In fact, personally, I think the current company calling itself S&W sucks, but I will continue to buy all the nice 3rd generation metal framed S&W pistols I can find, if that tells you anything. Good luck with your decision, hope this helps. Regards 18DAI.