I would have to agree that the Case-IH is better. Grain loss and grain quality are always problems with the conventional design. The rotors are better at threshing since grain has more chances to be threshed, since it will travel around the rotor about 3.5 times instead of passing the cylinder just once in a conventional. The conventional is better in the aspect that it will do a decent job no matter where it is set.The rotor can be poor if set wrong, but they are not hard to set, just takes a differnet theory.