Problem with blowback pellet is that the trigger has to index the magazine which in some instances ruins the feel. I have an Sig Sauer X5 which has the potential to be a great gun but the graunching of the trigger when it drags that belt around feels really awful. I say it has potential because I have the KWC version (which they call a 226 rather than an X5), blowback, adjustable sights but BB, which was one third of the cost of the Sig Sauer pellet version but I find it more accurate. The other point with the pellet versions is the lack of the slide lock on empty.
I haven’t tried a rotary magazine blow back, I assume the trigger feel is better than the belt ones. Of course for a pistol the rotary mag is more realistic in terms of shot count. The BB and belt mags are more like Hollywood action movie guns that never seem to need reloading!
Eric