I have heard great things about the super chargers on the Kompressor sports sedans.
Unfortunately the quality issues I have also heard about were specific to the little C class MBs and not the E or S classes?
My old man is into his Mercedes big time. Current rides are an e55 and clk rag top. He is obviously quite fond of this brand and knows his stuff. It is from him that I learned about the super charger, and the recent build quality issues specific to the lower end C class mercs.
My humble opinions formed from knowledge once removed
-bear