Like the title says, M&P9 will not drop magazines free. I have tried 4 genuine S&W mags and two of them will eject about 3/4" and stick while the others come out less. I probably should be in the habit of assuming mags will stick as a murphy's law scenario but it would be nice if they dropped free usually.
I created a support ticket on the S&W site so we will see if it is covered.
UPDATE:
Got my M&P9 back. The paper had a section highlighted saying they replaced the magazines I sent in. I wish I had pics of the magwell before I sent it in. They look to have opened up the entire mag well just a bit since even the mags I didn't send now drop free. Guys who own this pistol will know what I mean when I say the plastic "rails" in the well look to be smoothed out to make some room.
I am happy and even though customer service took a good bit of follow up on my part to get it sent in, everything turned out great. Thanks S&W