MW2 or MW3 connotation of ACR? Or, in other words, are you looking for lack of recoil or lack of flaw? M27 has the least recoil. If you're looking for the best AR then it is arguably the AN-94. If you have the trigger finger to capitalize on the intrinsic 2-round burst then you have a gun that gets select fire for free, basically. The FAL is a great competitor but the auto mode for select fire has been nerfed to normalcy.