I have both in my house.
Reliability and mechanics aside, the p07 duty feels 1000x better in the hand imo. It's like a glove and to me is near perfection comfort wise. The M&P is a full size and looks and feels twice the heft the semi-compact p07 duty does. Aftermarket support for the p07 is practically non-existant, although there really isn't much to upgrade. M&P is easy to find accessories for. Triggers are black and white, M&P is a striker fired pistol, p07 duty uses the omega trigger DA/SA system. Both are decent, nothing particularly special in either although I will say the Omega trigger is an improvement over a standard 75b style CZ trigger, which many think is already pretty decent. I'm not particularly fond of the 2 part trigger on the M&P, it's not a big deal but that little piece of flappy plastic annoys me, just personal preferance.
I have run the p07 duty hard through multiple courses until it was out of commission full of wet sand and the slide wouldn't even fully close. Q-tip and a field strip and it was good to go in minutes. It is dead reliable and has never otherwise failed me mechanically in any fashion. THe M&P I have not run as hard, but it also has never mechanically failed on me in any fashion either.
Honestly they are very different and I would recommend you try out both before making a choice. p07 duty is one of the extremely few polymer framed hammer fired guns on the market vs the full size striker fired M&P. Both are accurate, very different triggers, semi-compact p07 vs full size M&P, different amount of accessories available etc etc.