It looks like more of a some bends than a sharp crease in the picture, which leads me to think it would flatten out when you torque the head down, but that is what I think, not what I know, might not be a bad idea to send it back. The perfectionist thing is all relative I think, I might try to use it (would depend on closer personal inspection) so I am probably a little happy go lucky about such things, but I visited a guy a couple years ago who was about to put a head on an MGB (for the second time because of problems with the first try I might add) and the gasket was sitting in place, he was telling about how well he had cleaned everything up and prepped it, and how it was all ready to go back on, I could see chunks of I don't know what kind of debris sitting on the head gasket, dirt, carbon from the pistons, quite visible whatever it was, was horrified, politely pointed out that it might not be a bad idea to clean it up a little better, and he sort of half-heartedly replied that he supposed he might in a very "what's the big deal?" kind of way. I heard the car was inop a year or so later, though I did not hear why....