IF THIS IS THEIR GREAT CUSTOMER SERVICE, THIS IS THE LAST SMITH AND WESSON I WILL EVER BUY!!!!!!!!!!!
Hello all, I'll introduce myself with a different take on a similar situation.
I purchased my M&P15-22 on 02/05/2010 from GAT Guns in Dundee, IL. I was aware that some M&P15-22's had FTF and FTE issues, but I confident that I was buying a quality product and would not have any issues. I was mistaken.
Shortly after I picked up the rifle, down to the range for a quick clean, lube, and break in. Shortly after sighting in my Bushnell red-dot, I was having constant Failure to Feed FTF issues. Out of the 75-100 rounds I was able to put down range, I would guess that 1/5 were FTF. A final "double-tap" in the receiver was the last straw. Needless to say, I was not a happy camper, so I took it up with S&W directly per the advice of the helpful folks at GAT.
I spoke with a "Jeff" at Smith and Wesson and he was a true professional and a pleasure to deal with. 3-5 business days later, I received the shipping label, and then my M&P15-22 was off to S&W. I received the rifle back TODAY, and could not be more pleased with the results. 250 rounds down range earlier this evening, not a single FTF or FTE.
S&W stepped up, corrected all issues I identified, and returned it in a reasonable time-frame. I did not receive any free goodies, but they did replace the (5) magazines I sent with new ones. I was told their customer service is top notch. IT IS.

Major props to Smith and Wesson for standing behind their products, and having professional, helpful staff.
Figured I would share my experience FWIW.
Cheers!
Justin