At paper targets I can hit the head at 25 yard, but bad guys are not paper targets and some of them shoot back. So although I am confident on my marksmanship, is will go with the conventional thinking.
Also I worry about the legal ramifications of the "three bad guys, three shots to the head."
No doubt some namby pamby DA will say, "If you could shoot that accurately there was no reason to kill all three. A shot to the shoulder of the shooting hand is no more difficult to make than a shot to the head. Manslaughter."
So, if you do take down 3 bad guys with 3 shots to the head, it would be worthwhile to spray another 6 or more rounds in the same general direction to preclude that scenario. ("I shot 10 rounds, I got lucky with 3. I ain't no assassin.")