Consider a metering prism instead of just the WL. If you rack out at all, your gonna have to learn how to use the exposure compensation scale by the side of the bellows.
I owned the Pro-S. Loved the rotating back, didn't love the WL; I'm too short. When it came down to it my Crown Graphic was the same weight and gave a bigger neg with the ability to individualize development so the RB was sold off. If your using an RB indoors on a tripod for portraits it's a great camera. If you want to walk around with it on a shoulder strap (I've met people who have done this) I always felt it was better if you are tall with big hands. The camera is a little long tho. The common 127mm is a hell of a lens but DOF is better with a shorter lens and better utilized in suburbia.