[cdmulders]

Originally Posted by windowmaker

Does ACS really perform that much better?

I had my ACS springs installed by what I consider a very knowledgeable independent garage that not only specializes in BMWs, but successfully races them as well. I asked him the same question, and his answer was something like this: ACS springs are specifically tuned for BMWs, not only for ride and performance, but also to work well with the existing shocks and suspension. With my experience being only on ACS, I cannot compare to H&R or others, but I do find that the ride is better than OEM - it is just as smooth, but now more defined and more precise. I can take corners quicker and the apparent weight of the car seems to be somewhat reduced. Of note is that I also have the adaptive shocks and roll bars, and the ACS springs also seem to work very well with both of those systems too.

Because I can, here's a recent pic of my 535xi on ACS springs.