Originally Posted by NokTurNaL 330i
However, there is a side-effect. You will notice immediately how soft the rear subframe bushings are when you go over bumps but this will be the case even if you go with the aftermarket suspensions. This proves that the original suspension design had flaws. If you upgrade your suspension and SF bushings you will have a different machine with two personalities. One that doesn't mind being pushed hard and the other one that can chill out and just cruise.
Assume you're aware o'Koni FSD's, designed for your stock springs and at much lower cost. If you go that route, you'll have cash for subframe bushings + M arms, maybe front M sway, greatly improving performance and ride. Prob won't eliminate GAP, but that might be vanity. You'll appreciate disappearance o'pothole explosions.
DIY install saves, big time, well worth the trip. You're already on runflats, yes?