SIG Freak here
I own nine SIGs, two of which are P239s. I agree with the other posters: the P239 is great. One weird thing I learned is that I bought a Galco Summer Comfort holster for my 9mm P239, and my .40 S&W P239 SAS is slightly too fat to fit in the holster! I would have thought they were the same thickness, but not quite so.
While you're looking at SIGs, may I suggest you try to see one other model that is a new addition to their extensive lineup. The P229R SCT [Super Capacity Tactical]. Basically, it's their standard P229R, but it comes with a fiber optic night front sight, and Tritium rear sights. It also comes with four(!) 17-round 9mm magazines. All in a package not a whole lot bigger (but of course fatter) than a P239. Anyway, congratulations, and Happy Shopping.