not sure if its just on stage 1 but i have heard that whilst REVO and APR have worked around the issue by just reducing the boost limit before the 6000-6500 mark, it does not solve the issue of the valve springs. Just talked to my mechanic so he's going to see if he can get some VW service people to talk to otherwise he'll be the one to do the job
PS cant seem to reply to PMs but to danishmkvgti, my mechanic put the RS4 valve in to compensate for the higher boost requirements of the GIAC extreme flash. It gave a few kw's as well, since getting dynod, my k04 is pushing the most power out of all the other k04s including S3s , TTSs and GTIs with k04 conversions in Australia