Originally Posted by M54ccibo
Superlight is valve-less. Thinking that I'd probably go with the valves so that I can cut the sound back if needed.
The problem is according to Tom at EAS, he has seen the valves break and remain stuck in the open or closed setting. On the system he has on an M6 at their shop, the valve is stuck open all the time and believe me, its really really loud. This weekend Vic55 is coming to cars and coffee and he is running the Eisenmann race setup, it think you should hear that option before pulling the trigger.