IF you want to deal with the situation described usng a fire arm, you need to practice shooting off hand......like from your pocket. This takes practice X 10 in all aspects.....but .22 is cheep.
Lethality is NOT the object, getting rounds, by supprise, in the target is.
If your perp has several rounds of .22 LR in sensetive body parts ( like groin area, knees, or other joints.)....he'll quit.
If he don't you should have time to put a carefully aimed round between his running lights.
I would be supprised if such a confrontation would take place from more than 10 feet away. The .22 has little to no recoil, is easy to hold on target, and probably won't even light your jacket pocket on fire.
Wather P22 is ideal.....use top grade ammo to prevent jams.....cause you're gonna need 5 rounds in 4 seconds. Your perp will figure it out.,,,,you have 5 rounds left.
If not, keep your gun at home.
I do like the looks of that holster.