Probably a good thing it doesn't have phase detect on sensor, you will never get any banding
CD focus in generally more accurate, and any speed advantage would hardly be needed for portraits.
However, Panasonic G9 at one time had the fastest auto focus on any mirrorless, at .04 seconds, I guess that technology would be in the S1R as well.
Panasonic CD focus also includes a method of predicting which way to move the lens on moving subjects, nearly comparing with on sensor phase detect
It's a lovely camera, and they doo fell right in the hand