Buy a Glock!! Had to say it.
I have handled, shot all three brands. Both the XDm and M&P are good to go. I would be happy to own either or both.
My opinion:
M&P- Great ergonomics, lighter, lower bore axis. Trigger stinks.
XDm- I like the slim/long grip, good trigger, I personally shoot it better. Gun is "chunky" to me, I don't care for the grip safety. Made in Croatia.
Are there aftermarket options to make the trigger not stinky?
Apex. I have heard that they make the triggers on the M&P very nice. All of the M&Ps I have shot had the factory trigger. It was very gritty and just did not seem to break right for me. I do love the feel of the gun and it points very well. But I did not shoot the gun well at all. With a little bit of practice (lot of dry fire) I am sure that I would have a different opinion.
Interestingly enough if I had to pick a platform right now (Glock vs XDm vs M&P) it would probably be the M&P series of gun. They just feel that good in the hand. Also I like the fact that they have a .22 version available.
Which does everyone prefer?
Pros and Cons?