"Advantages of GBBR
These guns have an extreme fire rate compared to AEGs. The only other advantage I can think of would be that you can change your FPS of the gun."

i don't get it ? how gbbr can have more ROF then AEG . Cousin have AK74 with ROF 35 . I have APS UAR with no mods and with LiPO 11.1 batery it has 17-20 ROF .
HPA redline system can have ROF 40 . but there is not too many great mags that can feed over 40 .