there is no handgun that is a guaranteed "one shot stop" not even a 44 magnum or a high velocity 10mm. with a pistol i understand you have to hit the upper central nervous system to get instant results (like your example)
the fbi is moving down caliber from 40 s&w to 9mm
the hunters on FR can chime in here but it seems to me with larger more ferocious game you need a larger bullet
the increased size, weight and aggressiveness of urban criminals suggests to me that a pistol caliber downsizing is the wrong way to go.
they are downsizing due to weight, cost, and the prevalence of serious mind-altering drugs which for the lack of a better word — short circuit the nervous system — PCP is an excellent example it can 10 or more shots before the user even notices that he/she is shot.
You have to have a large supply of ammo for these types, the 9mm is the best choice if this is part of the criteria for choosing a new weapon.