I think Speedguner hit it on the head - the M&P 45 seems a little big to me for a ten round pistol.

The 40W&W is a much "handier' gun, and holds a few more rounds. I don't have a 357 M&P, so I can't comment directly, but it is the same size and has the same capacity of the 40 so it should be a handy gun for you.