40 S&W is a good caliber. And your choice of an M & P 40 is also excellent. I chose a CZ75B over the M & P. It's just a preference thing, as the CZ fits my hand better. I also have a S&W 410S 40 cal.
See what fits your hand the bests and what feels right;only you can tell.To the above poster just shows you we all have different opinions on same products I have SW99 in 45 which is basically same pistol as the walther and
I'd take that over any MP as I feel they are made much better than the MP.
To compare a MP and a glock this early is a bit much.The two MP I tries out had loose stuff in them rattling and they felt cheap and I own S&W products
and glad to see it's being well received.