I own a GBBR WE SCAR open bolt lisenced. Its as close as to realiztic as your going to get. I love it but I think there are 2 major cons. to them. One, when your playing down here most people have High or mid caps and if your in a situation that requires you to start firing like crazy your going to run out of ammo FAST! (No pun intended). And two,
if you are going to compensate by getting more mags they cost a fortune. I believe I paid like $40 or $45 a mag. Now, if your looking for a real milsim experience then this is it!