With your current mod's opening up your exhaust will do much more than an intake will. That said, if you want an intake I would get a Modshack VTDA or TTDA. Do some searches on Audiworld (the search will be down until sometime tomorrow) and you can find some test-data for the intake. It was created by an Audi TT driver after he did a decent amount of testing. I have yet to see any other intake manufacturer publish any data other than BS dynos (there may be some out there, but I've been unable to find it). The VTDA/TTDA are very popular amongst the TT crowd for a reason - it's produced repeatable, testable results.