the bright colours work better with big brakes but look naf on standard calipers. I'm toying with redoing mine. I have standard 4 piston calipers and 350mm discs on my merc thatll be similar to cossynuts but I think either silver with red lettering or black with silver lettering as red will look to Halfords boy racerish.
does your brakes have the m badge on them as standard? if not I wouldn't add it. as with Mercedes with amg , bmw have devalued the m badge with overusing it on almost everything.