How do people justify the "balance" they feel when they switch over to a new set of coil overs?
The M suspension is tested again and again on the Nurburgring for hundreds of laps to twit it right for the M3. The use of the "popo" chair, professional drivers and live data in order to produce the optimal balance for the car. Other than the benefit of lowering your car, I don't think KW will have a better insight of the M3 suspension geometry than the M department.
Let me ask, which system will you choose if they both provide the same ride height, M3 struts or KW coil overs?