I have a 637 that i wear in a don hume IWB holster. Its very comfortable.
As for shootability. Iv had a glock 17,23 a walther ppk , sig 239, m&p 9c among many orthers. I have alwase come back to one of the airweights either the 637 or the 642. It is without question, that it is tied as the most accurate hand gun i have ever owned. I once posted a vidio on youtube where I shot a 2.5" group at 23 yards free hand. If you practice with this gun you will be a far better all around shooter than if you went on to somthing else. SPEED is not realy an issue either. I can shoot five rounds at a 15 yard target as fast as pretty much any orther pistol that I named. If you dryfire alot and get used to the trigger you can become fast with it. [B]Reliability is great no ftf no fte. Every subcompact pistol i have owned has malfunctioned, Walther ppk, Keltek p11. Well there are orther options for sub compact semi autos i have never seen one that has never malfunction. Draw speedas it pertains to concealed carry can be no faster than with a revolver worn on the hip (IWB). The reason for this is you have a cylinder that is up against you body. The grip at this point is not up against you body like a semi auto would be. So you have a easy target to wrap your hand around.
For a CCW dont know of a more accurate, reliable, fast to the draw gun than a S&W snub nose