I would never ever recommend cat in a production environment. It is too unstable and doesn't support mocap very well. I'd prefer going over biped rather than working with cat :P. Cat will be good eventually but it still need more work.
I like biped's simple leg set up, very few parts to interact with. No IK/FK switching and the swivel is controlled by the rotation of the shin. Same for the elbows, its controlled by the forearm rotation. No second set of limbs to blend between and snap back and forth, no goofy look at swivel to worry about, just simple…