Quad Exhaust for B7 2.0TFSI Cabrio?

[Yellowtrophy]

I have a 2008 (B7) 2.0TFSI S-Line SE Cabriolet, and I an after an S4 style quad exhaust, to improve the looks, sound and performance (in that order!). I know Milltek do an aftermarket exhaust for my car (it is not quattro), but they only do a single tip on each side, which although bigger, is not what I'm after. Are there any other decent suppliers? Anyone with experience?
I know I will have to change the 'diffuser/valence' on the back bumper, but hopefully I'll be able to source the S4 version from somewhere.
Any help greatly appreciated.
Paul