According to E90Fleet, you're wrong about the brake pads.
"US M Sport models will not get the regular low dust, less bite US brake pads but will be fitted with Euro spec pads on the standard rotors.
US cars with the optional M Sport brakes fitted models will also receive the same Euro pads as their European counterparts."
This is without ordering the Msport Brake option.
http://www.f30post.com/forums/showthread.php?t=688550