How does the S&W CS40 compare to a Walther PPS

[Joescuba]

I been wanting to pick up a smaller pistol for concealed carry. I like the Chief Special on paper but I have never seen one. I like that it is a true double action as opposed to striker fired. How does it compare to the Walther PPS? Size width, length, weight. I carry a Colt Commander in 45. cal right now but would like something smaller in 9 mm or 40 cal.

Regards