Ignore the pull down in the final 200 rpm, i use a 6900 rpm pull and the final roll off is just exacerbated by the dyno pulling the revs to a standstill @ 6900rpm. These graphs are just a snapshot of a few hours of dyno tuning i do a few runs going to 7250 or 7500 depending on the car and setup and in the case the car was slowly nosing over after 6800 (like most turbos in this size) so there is no point revving the bejeseus out of a car endlessly whilst tuning (and to keep well clear of the limiter)... so i clip it 100 rpm after the roll off. I will make sure the graphs in the future continue to within 50rpm of the limiter.
Im not buying into any arguments here as our dyno is only used to test each of the hypergear turbos (we dont align ourselves with any brands), but if your worried about the sudden drop off dont be its no worse than any other similar sized offering from other companies.. what is true is they prefer higher boost levels 22psi is the sweet spot for peak power, i like to run them around 18-19psi on customers cars which will see about 15+rwkw less than their peak, i find it keeps the intake charge more stable.
From what ive seen they are hard to beat $$ per HP.