I own a CS45 and love it. Paid through the nose for it but I had followed prices closely and this was the first NEW in box I had found. I wouldn't trade it. The CS9 I have heard nothing but good things. I am just a fan of the 45acp and reload them. As for sub-compact 9s. If you are considering a Ruger LC9 I would look at the Kel-Tec PF9 as well.
The Ruger LC9 is almost an exact copy of the Kel-Tec PF-9 with enough small changes to keep them out of legal trouble. The Kel-Tec is a good pistol, every bit as good as the Ruger and $100 bucks cheaper.