My local Deere dealer has been hinting that Deere is about to introduce the equivalent of a 9750CTS combine, which "pretty-much" meets your specs. 65" cylinder, larger diameter twin rotors..., er..., tines, but with no prethreshing cylinder! I think it would still give a CAT (Claas) a good run for it's money, especially if they put enough horsepower into the machine!