As I understand it, you can use (4) front rims, in a non-staggered setup without problems. That refers to the 19-inch wheels. However, it sounds like you are looking at a complete set taken off an M3, in which case, sounds like you'd better do some fender rolling.
This guy is rocking (4) front wheels on his 330.
http://www.e90post.com/forums/showthread.php?t=755690