Which holset are you running?
It used to be the in thing on some of the audi sites to get a holset from America for a cheap reliable turbo. I have been thinking about getting one since being in America now it would be cheaper.
Though years ago a guy I used to know was running remapped rs2 spec so circa 380bhp and managed a 2.6ish second 0-60 so have been thinking about sticking with that setup.
edit - Car was a audi s2 avant 2.2 20v 6 speed, time was at bruntingthorpe at gti international. Owner now last I heard works for MRC and his name is Ben. He used to drive the car like he stole it with no mechanical sympathy

Nice guy, been a while since I chatted with him.