We have a S&W M&P (in addition to several LMT's, LWRC's, PWS) and it runs just as well. We use it for training as a demo gun and for sims/UTM work. For a base model AR, it holds up well, eats whatever ammo we put through it (we do not run Wolf of HSM), and is still accureate enough (1.5 MOA with a EO Tech), even on full auto. If you don't have $1600 to drop into a LMT or other (although I suggest saving up and doing so), $700-800 on a Smith isn't a bad choice. S&W's customer service is well known, their gunsmiths/builders have more time in the business than anyone else (the "rookie" there has been with them for over 25 years). You don't need an expensive gun to become a great shooter or to enjoy the sport.
Stay safe...