Originally Posted by clarence
They're identical in technical spec, unless u're talking abt 2NH for 320i & below.
All parts are interchangeable between the 2 systems, so swapping discs are fine.
OEM US Msports do not get M Performance brakes.
I measured my front 335i Msport rotors and they are not the 14.5" apprx diameter that are part of the M Perf brakes.
My rotors are somewhere around 13.5".
Also, my rear rotors are smaller than the M Perf rears.