I have a used 642 I bought four years ago that had the flaking clearcoat problem, which I made worse by trying to sand under the grip
It isn't so much how the gun looks, it's that it lets the moisture get in and mess things up. I called S&W and they sent me a prepaid Fedex label. I sent the pistol in with a brief note and got it back three weeks later looking like new, for free.