dont go oem, and save money.. theres no fitment issues... if you go with the right brand. painting and install , you are going to have to pay regardless if you get oem or not.
bmw canada quoted me $4000 for front and rear
i got it done for $2500
saved over $1500
actually what i wouldve done is order the parts off of ikonmotorsports you can find his postings here
http://f30.bimmerpost.com/forums/forumdisplay.php?f=476
(sponsored seller) he sells bumpers and offers paint service for a cheap price ($250) so you just gotta worry about the install when you get the part
pics below