M&P !!!
As the owner of a M&P-9 Full size, XD-9 Tactical, and former Glock 17 owner I feel that I should weigh in here.
Personally, I prefer the feel and grip angle of the M&P. After shooting my G17 for a year, the grip angle still felt off and I couldn't shoot it well without really concentrating on my aim. After shooting my wifes XD-9 tactical a few times, I realized thatI could shoot it more more relaxed and still shoot effectively. This prompted me to start searching for a replacement for my Glock and sell it.
I shot and handled every 9mm that I could get a hold of, from 1911's, to Sigs, to Taurus, to HK, Steyr, Kahr, Star, Kel-Tec, Hi Point, Walther, Baby Eagle, S&W, Beretta, CZ, Llama, Springfiled, etc.
The full size M&P felt perfectly natural to me from the minute that I picked it up. When I shoot it it feel slike a natural extension of my hand. I immediately put my G17 up for sale, bought the M&P and haven't looked back.