The ARES PPSh-41 replica also features the same style blowback mechanism.  It comes with a 2000-round high capacity drum magazine.  The AEG offers quick takedown as well.  One simply has to pull back the fake bolt and depress the rear latch, and the stamped steel upper receiver flips open.  From the various firearm enthusiasts at the show who have handled the real PPSh-41, the consensus was that the appearance and feel of the ARES replica were spot-on.