Got my hands on a type II ... it is a bit different from the original. Aside from the aperture click disable feature (horribly over engineered IMO) the lens is heavier (~1 ounce more) the focus and aperture barrels are larger in diameter (0.130" & 0.080" increase in diameter for aperture and focus, respectively). The aperture click is markedly louder and feels remarkably clunky compared to the original. When the click is disabled there is still a loud noise made when the ends of travel on the aperture ring are met. Optically - looks to be identical to the original. Not huge changes but for me a real problem for reasons mostly unrelated to general use.