Induction Kit for Cooper S

I'm thinking about buying an induction kit for my Hartge Cooper S and just wondered who on here has one fitted? My car has 4 pipes and makes a fair rumble just now, I'm just a bit concerned the induction kit will make it really loud.

I'd really appreciate your comments on make, price, performance,noise warranty etc

Thanks

I have the Piper-X fitted which adds a little more oomp, as for noise, there is not really any difference. As for warranty, both John Clarks and Grassicks are sensible about these sort of mods when it comes to warranty work. I think Alan had an induction kit fitted on his Hartge but took it off. But as for buying one, I've no doubt John is the man to see;)

I've also got a Piper X on my MCS - funnily enough - supplied by John:D