depends on the carbon fiber thats used some look different then others (wet and dry carbon) i have always liked a gunmetal or charcoal color with carbon fiber
I am planning on getting real cf parts, but for smaller accents like the grill and stuff. But the carbon fiber is wet I think because its shiny in the pictures. What color would match best with that? The link of the vinyl you sent me seems like its a dull carbon fiber which probably wont match with the wet carbon fiber?
I sold my CF lip to a guy with a grey MS3 and it matched really close. Your best bet would be to go to a reputable body shop and browse there paint catolog. Thats what I did when I was trying to pick out a color for my wheels. If there a good shop, theyll be willing to do the leg work and use your car as reference. Otherwise metro grey is really close.
I hope he doesnt mind, but here is the link from one of his posts with my old lip for color reference
Anything that is pretty much dark in color like a gun metal gray or black usually goes well with the carbon fiber. You should definitely take Strick's advice and go to a shop and have them match the carbon fiber with their color catalogue.