Well, size wise the CS 45 is going to win because it is smaller, you give up on shot of capacity, that may or may not be a big deal.
But......
The CS 45 comes with rubber grips only, which are a pain to deal with when it comes to cover garments hanging on the rubber and what have you. The good news there is that there have been a number of people here on the board that have sucessfully manufactured a set of stock Delrin grips from a larger 4506 grip. If you don't feel handy and all that, Big Dog here on the board has manufactured a number of sets of Delrins for people. So there you have it. I like my Chief well enough, but I would love to have a stainless 457 or a 4516, just to round out my 45 Smith carry system, I have the 4566 and the Chief now and I want an in between gun.