What's the best one to get ?
s1 still has a Bailey trumpet one lolNone. Dump valves are not required (unless you are 18 and wear sports gear in the street and a baseball cap backwards!) A recirc valve offers genuine improvements and helps performance and makes a sound that better suits the car....
is it the sound of the dump valve you're after? how about a turbo smart recircWill a recirc valve get rid of the mouse under the bonnet aswell?