Right guys I've got a full system made by longlife in carshalton. Fantastic exhaust and looks great. Was made for my 1.8 (also fits a 2.0 xsi) but now I've broken that for parts, I'm going to get something a bit different for the 6.
It cost me just under £500 new back in January 2012 and I still have all the invoices/warranty that I will transfer to the new owner. (full lifetime warranty on exhaust except for cat. That's 1 year)
I spoke to longlife and they said they will modify it to fit a gti manifold for £30-40.




Tip is 3.5" iirc but I also have a 2.5" that I will chuck in. If your handy with a welder, will only take a few minutes to swap although the 3 is a perfect fit for the bumper cut out.

After £300 for it ONO. Based in Epsom and can't post due to size but can drive to meet or deliver to an extent.

Unfortunately it's standard mate. Couldn't afford anything more!