Originally Posted by JetBlack5OC
Both Eibach and H&R have a lot of racing credentials.
I have read a lot of reviews from M5 members with the Eibach Pro-kits. They say they feel no difference at all in ride quality. I had H&R's on a 3-series a few years back. It felt a little bouncy at times. I see why you like the H&R's, by looking at your screen name.
Yu are correct, I had an Eibach pro adjustable suspension kit on an E39M5 and changed it for a Bilstein PSS9 after 30k of enjoyable miles. The H&R adjustable kit was reputedly harder than the Bilstein, which was harder than the Eibach. I undertand that H&R are usually stiffer than Eibach for their spring kits BUT this is not always the case.
The ride of the H&R's with 18's is much better than a stock e46M3 on 19's. I know I had one and my friend still have a sub 30k miler we compared and debated the suspension between the two cars yesterday !
My point here is don't reject the H&R's on stiffness as they really are not too stiff for the E92 and IMO work extremely well