Originally Posted by M3PO
Assuming that your car is the silver one in your signature, I would skip it. Metallic silver paint is almost impossible to match. I had a nightmare experience with my last car, a metallic silver (much like your M3) 350Z. It was painted three times using top-of-the-line paint (PPG), the first time by the shop, then by the auto paint supply store, and finally by a PPG rep. It didn't matter. I saw the same thing on every silver 350Z with a body kit where only the bumpers and skirts were painted.
I'll be SHOCKED if your car comes back without a noticeable mismatch.
this is common on almost all cars. It is exaggerated w/ silvers but most cars bumpers are not even painted in the same place as the cars and the bumpers are also made of a diff substrate.. They're is so many variables. Some shops want to blend fenders and 1/4 when painting bumpers for color match but it is not warranted as most never match from the factory anyway. The problem is that the people scrutinize the car much more when it is back from the body shop and that's when they notice the diff colors.
Fact; even GM released something stating this to customers when the new camaro came out. If you look at the hard angle of the 1/4 panel on a new camaro to the door line depending on the color you can see a variance and customers would notice.
Anyways, chips are gonna happen, live with them, or repaint the bumpers; choice is yours!