I wonder if real HK trigger groups could fit on that, I've always wanted an early MP5 GBB with SEF, thin hand guards and straight mags (although the straight mags are not really a possibility with this gun)
Except its not really open bolt, still has a brass tube for a BCG... lame. Plus the VFC m4's have a ton of problems and still no aftermarket parts. If their previous gbb foray is any indication of whats in store I'll be waiting for WE to throw their open bolt system into it. At least then RA tech will jump on the bandwagon and make an NPAS.