What is wrong with a M&P it is the best polymer pistol in my opinion.
Not a thing wrong with the M&P...I own a couple. One is a full size 9mm, and the other is an M&P 45. Glock is still my first choice in fantastic plastic, but the daggum M&P is a close second. Once the not-too-terrible M&P trigger can be made as nice as a Glock with a Ghost Rocket and a little polishing...the M&P will be similarly as groovy as the Glock.
The XD...well...let us just say, it is STILL the "Croatian Abomination". It just doesn't shoot well for me, and that is the yard stick by which I must measure any pistol.
In HUNDREDS of thousands of rounds through Glocks, I have experienced only TWO failures, and they were both Sherer Magazine related. PATOOEY on the Sherer mags.