Fitted my new powervalve system this morning, spent the other half of the day looking for reasons to stay out in the car with a MASSIVE grin on my face! System sounds a little and I really mean a little over standard when driving around normally, no droan, I repeat no droan at all on motorway cruising, amazing note when on boost and the valve opens. Not a raspy or tinny sound, but a real deep, crisp tuned note. To say I'm impressed is an understatement!