So I've had my iPhone 6 since launch day and since then have sometimes had it in a case, sometimes not. I noticed a small spot in the corner on the back that it seems like the finish has begun to rub off. I noticed this on my coworker's 5S in Space Gray as well, and it was actually much worse. Has anyone else noticed or would it be considered some kind of defect? I never noticed any problems with my white iPhone 5.