I bought it because of it's size. My Walther P22 feels like a child's toy in my hands, and the Ruger SR22 is similar in size. The M&P has the feel of a full-size pistol, which is what I wanted. My only complaint is it only comes with one mag and the mags are very expensive.
NRA Certified Pistol Instructor & RSO, IDPA Sharpshooter, Project Appleseed Rifleman
Member NRA, GOA, SAF, VCDL