I just put in Bilsteins Heavy Duty Models all around using my stock springs and they are fine. They raise the car a bit but ride smooth and firm like a new car. Bilstein sport shocks are for the real performance handling types as they require stiffer springs to work right. They are way to stiff for the roads I drive on or what I expect in a luxury car. Bilstein also has a new Touring shock that is an entry level lower cost shock but I did not dare try them. They are only a little less so why chance it.