I'm trying to think of a colour the GT-R looks bad in, it's difficult though. My Spec V is MNP III with a set of alloys that were gold to begin with, I'm not sure which they are. It also has an unpainted CF bonnet, I had thought the three colours wouldn't really match, but, they do.
Plus I'm just really loving coloured wheels right now, I used to think only black or white (on a Honda Type R) looked good, but I have a set of Taiga Green Metallic wheels on my matte black AZ-1 that have convinced me otherwise.