I'm partial to the glocks but the m&p's are great too. It basically comes down to which one is more comfortable in your hand.
The Glock 17 fits better than any glove I have ever worn. First shot through mine was at about 30 yards at a crow as I was driving across the pasture. He kept watching me so I just took aim and fired. I bet I could not repeat that again in a 100 shots, especially since I never stopped the truck to shoot. I took that as an omen. That is why the 17 is my go to.