I was tired of having my driver's side seat repaired, so I bought the covers and installed one on the driver's side. I did not change the foam. So I have a factory original passenger's side and the replacement on the driver's side. I don't think anyone notice's any difference. I least I can't tell the difference between them.
I will change out the passenger's side when I get a rip or damage in it. I think it is like the front tire on my old motorcycle... it never saw much use although the rear had a lot! I don't drive like like anymore too old?!