Just buy the same brakes BMW used for the Z4 M and M3 CSL. A little bigger rotors, drilled, and definitely more bite. Turner Motorsports sells a kit to install them.
'08 Carrera S 6MT Guards Red/Black ext leather, Carbon fiber pkg, sport exh, sport chrono +, PASM, Nav, Bose, 19" forged turbos, red tranny tunnel
'07 MV Agusta F4 1000 R 1+1, Corse Red/Silver, RG3 race pipes and factory race ECU