Gran Turismo Blau < (the colour in the Mercedes-Benz Dealership) is the nicest shade of Blue ever.
Black with black wheels - Simple combination, makes it look like a beast.
Isotope Green ? < Lotus Evora paint, I think it's called that. That Bright Lime Green/Yellow matched with black wheels makes it look like the Mercedes-Benz SLS E Cell (Electric Version of normal SLS AMG) I use it for drifting and when the sun hits off the paint it looks great!
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Just re-read the OP and I think Matte Black or Matte White (if that's a colour) would be best. However I strongly believe that you should also consider the ones above with no aerodynamics and a coloured hood.
I have a "GT3" Style SLS AMG with the Coloured Carbon Hood and Wings, and I have it in just a Glossy Black with the sane colour wheels, looks great!