I would be ok with .380 as an option for deep concealment. I wouldnt, however, choose the NAA - I have heard too many respected opinions about the quality and reliability. Personally, I chose a Kel-Tec PF-9mm for concealed carry. Its not quite a pocket gun, but with the attached clip it nearly disappears behind my belt. In the future I may pickup the Kel-Tec P3-AT (.380) as a deep concealment pocket gun.
I chose the Kel-Tec because of size, but some of the guns on your list are bigger and thicker (Kahr, Springfield and S&W) - if you dont mind the thickness, have you considered a baby Glock? They come in just about any caliber and have the Glock reliability factor.