You are going to get two types of responses...as this was just asked recently.

The first one, which I fall under, is this is a brand new gun. I'd call S&W and send it back. If I pay for a new car, I don't want to take delivery of it with a scratch on it. I realize the gun (or car) will work absolutely fine even with said defect. But that's the point of buying new.

Now, the second line of thinking will be...why the fuss? It'll shoot fine, it'll do nothing for reliability and/or longevity, so why bother just go shoot it.

That's really your call. But you'll get plenty of responses for both points of view, neither are right or wrong.