i think it looks just fine -- i dont mind the stock bumper too much but then again mine is flat black. the contrast on the white is great. i have thought about changing my bumper etc but not sure it would really make much visual difference.
love to see another local and a diesel owner no less! im in your area all the time - if you guys end up doing something... hopefully in better weather though so i can at least get my summer wheels back on.
as far as the retrofit sensor -- does it integrate with idrive at all? i might put in a rear camera instead...