Having seen Michael Janich on TV, I can tell you that if your assailant is an actual trained knife fighter, you have no chance with a gun. None. You'll be a bloody mess on the ground before you even know what has happened.

Luckily, few trained knife fighters are bad guys. You have some chance against creeps with knives. Note that 50% of knife attacks are fatal, whereas 90% of shooting victims don't die from it. It is much better to be shot than stabbed.

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I've still got it made.