Excellent, I used Profusion exhausts on a e61 545i estate. I had them install straight pipes for me and remove mufflers. It was ok for a while but like you say it gets a little wearing. The valve option is great
If I remember correctly Raj, was the guy I delt with. Little industrial estate in around Heathrow.
Your 55k sounds a beast btw

The cost wasn't to bad either and to have the opening closing at the press of a switch is spot on. Nice set up.
Sorry it could be Jag, who I dealt with. Really know there stuff and was really helpful in listening to what sort of sound I was after. And great work also.