One option is also to go for Dark Shadow Metallic. That's was the original color of my M-sport 535i's part and I got the OEM M5 diffuser painted withe the same color. I have been happy with that choice.
For F11, this color is in my opinion much better choice than body color. I was also considering gloss black as another option but thought it's having even too much contrast to the body color. Might be a different case in F10 or in a car with darker body color though.
