6906 is a great gun, I enjoy mine quite a bit. You can make it a bit "smaller" for CCW if you replace the factory pinky baseplate with a flat baseplate off a 5906. As you saw the full size mags for the 59 series work great, so you can actually have a 17- round backup mag (using Mec Gar mags).

And the CS series are kickass little guns. Get one!