UPDATE: Ok, so today I was going to carry the pistol in question to a gunsmith to take a look before I called S&W, but decided before I did I would put a few rounds thru them first to see for myself.
First, I took 3 each 6 rd mags, and put 18 rounds thru MY gun as fast as I could - zero misfires, no issues.
Then, I reloaded those 3 mags, and did the same with my wife's gun - interestingly enough, ZERO MISFIRES, no issues. Then I took shot an entire box of .380, reloading the mags and again shooting as fast as I could. Again, ZERO misfires. Not a single misfire in my wife's gun. I looked at the primer strike...dead center and plenty deep enough.
So I called the guy that shot with my wife on Friday, and asked him if HE PERSONALLY shot or experienced any misfires with my wife's pistol - "NO" he didn't shoot it. So I told him I think she's limp-wristing it; his response was that he watched her shoot a entire box with MY pistol with no misfires, but hers did. So the question begs, "how could she limp-wrist one and not the other?". I even tried to limp-wrist her gun (but it's not in my nature to limp-wrist anything)
I don't think there's anything wrong with the pistol, I think my wife's grip is the culprit. The next thing to do is take a box and both guns and her to the range, and hand her mine and say "Here's your gun" (she'd never tell the difference but I can) and see what happens....