Spoke to Miltek lastweek, spoke to Beckie i beleive! They are very very nice and friendly compared to other companies i have rang, they quoted around £435 for the R32 Style Exhausts for my GTI and i think it was a cat back but not sure...whats the difference between a turbo back and a cat back exhaust if you dont mind me asking 
cat back is a part system from the catalytic converter. the Turbo back system is the full exhaust and includes the downpipe from the engine, a free breathing sports catalytic converter, the back box and the tips. The full system gives better breathing for the engine and as a result better response and a few more bhp when used in conjunction with a good remap.
Oettinger quote 305bhp for a remap and 330bhp for a remap, full exhaust and ram air system. So it gives about 25 extra horsies when used in conjunction with the ram air and a remap
