I watched a review of the gun on YouTube claim that the blowback is weaker than expected but it must be the previous model, as this gun blowback so powerful it almost feel like real one. One gas cartridge would last an average of 7 mag in a cold day of Texas. The uper part is metal. Grip is plastic and feel a bit cheap made. I think this gun’s barrel doesn’t support supressor. Mag release is easy, maybe too easy I drop it on the field once and had my team look for it. The mag is metal and heavy feel. The function I live about this gun is it automatically lock the slider when mag is empty. Best bang for the buck pistol on eBay. I decided to get this after read a bunch of reviews on Google.