I thought the rear hubs go something along these lines (and please correct me if I'm wrong):
A hub use in low tractions condition, more locked in rear, more roll, less steering
B hub use in medium traction, car is more neutral?
C hub use in high traction (clay, groove) rear end is loose, improves steering less roll

All this is based on the roll center postion and ball studs added or removed from U brace and location moved in or out on the hub. Seems that the major change is to go from A to C hub and back but not alot of B hub users.