You do realize that 1 hit headshot was 99% negligible right? You had to be CZ range to get that headshot, and in case you don't even know that; it's stupid close. It's an upgraded M4, it should have that perk as it's an upgrade.
Also as an avid SG user, I heavily disagree with the nerf; no one is using it near enough like the AUG for it to be even ready to be considered nerf worthy, and it's completely so niche for that exact reason that until people actually care enough to start using it 24/7, then it should be. Until then, I'm going to laugh as these sheep that followed pros for years yet again failed to realize 2 game changing rifles existed, but now want them nerfed all of a sudden lmfao.