Thanks for the info, i just read all 18 pages of the ECU/Software upgrade thread and I'm about to barf from digesting all that info... I've also got a nice headache to go with all this new knowledge. I found a shop close by that is an official APR dealer, i'm going to work with them to get the APR stage 1 ECU software. They also had a wave file from the stealth APR turbo back exhaust system, and i really liked the way it sounded... however, 1300 bucks for a little boost and a huge chance i'll never pass smog again... i'll take a raincheck.
I read on that ECU thread about there being a possible issue with the Diverter Valve (DV), and I noticed at the APR dealer shop near me, they sell a type "C" diverter valve, which is supposed to be stronger than the factory type "B" diverter valve... I guess i should try and use that good old search button again to find out if my late '07 GTI 4 door has the Type "B" from the factory or the type "C" ...
I also saw this shop sells the Carbonio intake that keeps the stock engine cover... that sounds kind of interesting to me although i keep reading that the intakes don't do much for the performance. I may just throw a K+N stock filter replacement in after i get a couple thousand miles on my Fast.