All your answers here:
http://www.realoem.com/bmw/showparts...71&hg=51&fg=20


Arch flares are the same for E70 with or without runnig boards, depending on wheels. It is a DIY job, and as far as I remember from my E53 it takes a bout 2 hrs. (But then it was with the wheel arches). In terms of aesthetics, it's a decision you have to make. When I did it form my E53 (the car came with aluminum boards), I paid for the std kit, only to come back to the alu option because it looked more beefed up....Cheers!