I would not expect you to find too many stories that would substantiate mine, in many cases they go unreported or don't even get past the police blotter, as in Detroit where the over 50% of the crimes are unreported and only 8% of the serious crimes get in the news, either print or radio/tv.
One reason to use a heavy caliber is simply that every situation is different for everyone and it is better to limit the chances of not stopping someone. (there is another reason at the end of this post.) In my case the fact that the guy who assaulted me was dressed for cold temperature (heavy clothing) and the likeliness of me getting a head shot was slim to none. I didn't prepare myself for him but maybe I should have.
Irregardless of my situation, the problem is that the 22 is a high velocity round, with lot less energy then say a 223. The round itself can do a lot of damage with soft tissue (a round of choice for hit men/women because once the energy is reduced within the brain material, it can't penetrate the skull - sorry for the graphic detail) and even some medium material but hard material it does not penetrate like say a 223.
But the real issue here is the clothing and I got to point out that in fact my situation played out just like the situation that the soliders faced in the Philippine Insurrection (aka Philippine-American war). The military adopted the 38 (I think that was the caliber) that replaced the 45 colt that they used for years. While fighting the Americans in the Philippines, the Moro warriors used a method of protection of wrapping them in tightly fitting heavy cloth to prevent the penetration of the bullet. The fact that even the 30-40 Krag could not put the Moro warriors down in many cases, the military was forced into returning to a larger caliber with more energy behind the bullet to penetrate the protection. Once the 45ACP was introduced, the US wounded and killed dropped.
Now speaking about the round itself, what makes a 22LR very dangerous is the simple fact that it is of a high velocity and tends to be easily change directions by hitting something hard. One reason that many are killed by it is that is will ricochet within the body but won't penetrate the muscle or skin.
But regardless what you can say about a 22LR, it is not a gun for protection in a situation where you have to react. As I mentioned it is a high velocity round and firing a few without knowing what is going on around you is dangerous and irresponsible. With a 9MM it is limited to the distance it travels, which means the guy down the street walking his dog has a less chance of getting his with a 9MM then if you used a 22LR.