I have one and have shot, maybe, 300 rounds, since installing on a standard Scorpion 7.72" barrel. The 300 rounds were a combination of suppressed (reason for ordering) and unsuppressed.
A little stiffer cocking handle effort and little less gas in the face is about all I can recall.
Shipping straight from Ascalon took quite a while. I think they are sold in the USA now.