That's cheating indeed. Yesterday a guy messaged me after a doubles match saying that I had a nice "toy" and said something about "rapid fire control". I didn't get it at the time, thought he was praising me for controlling well the hawksaw, which is a fast firing gun, lmao... guess he intended to say "controller" instead.
The gun kills in 0.80 seconds if all headshots land while fired at full RoF (according to a chart I've seen), but in this video it's simply too fast.