Since I received my license to carry 19 months ago, my primary carry handgun has been my M&P 40c. It carries easily in my pocket with a DeSantis Nemesis holster, or in my 5.11 holster shirt, or in my Galco IWB holster. Its 10+1 capacity is greater than most carry guns, and while it initially feels a bit heavy, it becomes quite tolerable after a couple of days. It is very accurate out to 15 yards and it has been totally reliable through 6500 rounds. Its only shortcomings are a trigger action that is a bit heavier than I would like (though that's not necessarily a bad thing with a carry gun), and the lack of a second-strike capability (though it's never failed to fire). It is also the perfect size for my nightstand.
I'm always open to the possibility of replacing it with a better carry gun, but so far, I haven't found one. Kudos to Smith & Wesson for a great design.