The NAA .22s are what might be considered a "deep concealment" firearm. They are small enough that even if someone is knowledgeable about concealed weapons, there's a good chance that they will not be able to tell you are carrying. From a ballistics standpoint though, they are best considered as a long range ice pick. Poke a cylinder worth of holes in someone and run the other way, hoping that it either slows them down or they bleed out before they catch you. If you are going to be some place where they frown on concealed carry, they are better than nothing.