This is somewhat out of curiosity although someday I would like to purchase one of these lenses when not wanting to carry the bulk and weight of my 70-200 2.8 lens. Currently using a crop body. It seems the 85 is extremely popular and an excellent lens. Yet, I hear little of the 100 2.0 lens. So I am wondering why the preference of the 85 to the 100? I am not criticizing, but curious why the 85 is seemingly more popular. The price has risen on the 85 so much so that it cost nearly the same amount as the 100. I assume that is due to the demand and popularity of the 85. I did not compare the physical dimensions, nor the weight or image quality of these lenses.