I just got a new 2012 535i last week and dislike the gap in the fender and the body roll.
Looking at the H&R springs vs the ACS Springs as far as drop is concerned.
After a lot of research I came to the conclusion that I would go with the H&R because the drop is lower and I'd like a stiffer ride being I do not have a sport package.
The H&R lowers the car by 1.4" front and 1.3" rear while the ACS lowers the car 25mm in inches that converts to 0.984 which is less then an inch.
For me thats not enough.
CURRENT: 2012 535I
RETIRED : 2011 135I
RETIRED : 2003 540I
RIP : 2003 M3