MopedCafe has sold a lot of A55 bikes, and I haven't noticed a rev limiter on any of these bikes. However, I did have a 05 Streetmate that seemed to retard at about 9500RPM.
MopedCafe also has the Technigas pipe and the Airsal. We haven't done a complete tuning (as in carb, intake, pipe and kit) yet, but the kit performs very well as a bolt on with the "European" pipe installed. Ran a 68 jet, I believe.