This kit is pretty aggressive. Requires some other quite serious modifications, for example for their top end, 480PS (472hp) tune, your going to need some serious gearbox upgrades for both manual (uprated clutch) and DSG (additional friction discs needed, not included in price of kit). They make some pretty massive induction and exhaust changes with oversized pipes before and after the turbo charger (downpipe, larger diameter exhaust etc) and an overhaul of the ECU and TCU software. Not sure on what replacement turbo they supply, looks like you need to contact them for more information.
GPS times quoted aren't bad but I've seen one from a Golf R quoted at 2.98 GPS. Was posted here a while back or at one of the VW sites, had less modifications than this kit proposes. They also offer a brake and suspension upgrade (additional cost!!) which would make track use a much better experience. Not sure if suspension provided is a coilover replacement or just springs, if it's the latter, maybe the above is not as relevant.
If you want a fun track day car then you need to think about your cars suspension geometry just as much as you think about the engine. The S3 doesn't have great damping on the stock setup (mag ride), so a coilover replacement would be a good place to start, get an adjustable set and your good to go. If you want to go all the way, replace your bushings and control arms with improved aftermarket replacements from people like SuperPro and get a decent 4wheel alignment!
