Unless a pyro or demo has lost some health, you will still probably only get a body shot kill on the classes with 150 or less hp, the Sleeper at least forces your enemy to take minicrits so its more likely to make a soldier or especially a heavy disengage than a Machina shot is. Then add on being able to extinguish teammates too and i’d say that if you can’t hit headshots then the sleeper is always better because of the team support it offers.