Yes I've seen some videos on the knife to gun comparisons. Even tried it myself with a rubber knife and a guy with a holstered replica gun. Hard to believe that the guy with the knife will take the guy with the gun when 21 feet or less away from each other. It was produced for law enforcement as most everyone of them said that was b.s. and were not afraid of someone who's even 10ft away. The guy with the knife knows this too as a rule. The idea is when a 'situation' begins the guy with the holstered gun doesn't know the intentions of the guy he's asked to stop that may be a threat. So when the guy with the knife attacks, the reality is the guy with the gun needs a few seconds to get his gun out, aim and fire. Try running 21 feet from a dead stop sometime and see how long it takes. Bottom line:not long and much faster than someone trying to quickly and emotionally remove a gun from his holster, aim and fire it. The knife wins everytime. And the knife never jams or runs out of ammo and like the Energizer Bunny just keeps on going. I have a lot more respect for knives ever since.