I am coming up on 165,000 miles on my 04 330ci zhp, and I figured I needed a new suspension. When I took the old (stock) suspension out, OMG they were completely dead. I mean completely... leaking fluid and everything. I replaced them with new koni FSD suspension kit which came with shocks on all 4 points, as well as springs (about $800 for the set). Wow did they make a difference! I highly suggest reading up on these magical things. The car drives better than if it was new. I tested it on a bumpy road and I could hardly feel the bumps! I did some sharp turns and the car stays straight with NO roll. The car is perfect for AutoX! The KONI FSDs are well worth the investment, especially if you are replacing your suspension anyway. Has the handling of a performance suspension as well as extreme comfort. Definitely the best of two worlds with no tradeoff.