I have one fitted to mine but i`m not sure what manufacture it is. There is also a thread somewhere in the technical part of the forum which progressed the subject with regards to performance or advantages to be gained. I think the outcome was basically that it removed a lot of stress from the turbos however on a personal note you simply must fit one for the noise alone!!!
Sounds a bit like an HGV when driven softly but when accelerating in anger it sounds simply fantastic!!!!