Have you ever been in a car with kw?
You can use for getting grocery's, track, driving kid to school.
The KW ride better then oem sport suspension.
Kw also has LIFE TIME warranty, so that is longer then 4 years.
Have you done any research on suspension before you make comments?
How are you suppose to beat the crap out of your car with spring that retain oem spring rate that your oem damper was designed for? I confused, Dinan reaseach what spring goes with your oem damper? If so your car came with the right spring already, BMW install it at the factory.