I just recently received the RRS BPC-16 and put my 553 on for a test ride. It is nice. The panner works very smoothly, I would say it is on par with the Outdoorsman's regular panhead with this lightweight scope. But of course, to tilt requires using the ball joint. With the ball joint, the lever lock can be adjusted so that the tension range can be shifted. Inside the range, I feel there's a forgiving zone that allows decently smooth maneuverability when pushing the scope and enough tension to hold its place when not. Definitely not as smooth as it's panning, but well enough to work that way.
Given its extreme lightweight (4.4oz), smooth panner, and strong locking with zero shift, I think I'll be very happy with it.