Not yet, but I was at my LGS talking with one of the men who works there, who happens to be one of the gunsmiths (he's the guy who's put the sights on my XDm pistols). He wasn't giving me the I-read-on-the-internet-bullsmeg that most gunshop workers give, he was giving me the "I fix guns for a living, these (Glocks, Rugers, and Springfields) come in to have sights put on, and these (Smith's and Kel-Tec subcompacts) come in to be repaired."
He then proceeded to tell me exactly where the weak point was on the different guns, in the M&P it was that the plastic hinged trigger tended to have pins break. He then went on to say that if they used the Glock-style trigger or if they used a metal trigger with metal pins, that the gun would probably be perfect. He also said that while he prefers the Glock Gen 3, the Gen 4 would probably be better for me (as a lefty), and he doesn't know why they went without ambi slide release. He did agree with me that the features of the M&P fit what I wanted to, but the life expectancy of the trigger was a liability.