Quote Originally Posted by Joel Eade View Post
When we swapped lenses for a while at Laguna Seca the images I took with his EF 100-400 II were perfectly sharp and I would not say there is enough difference in sharpness between it and the RF 100-500 to entice anyone to switch.
It sounds like my debate to buy it is the same as I had with the EF 100-400 II. I gave the 100-400 I version to my brother when I bought my first 500mm. My thinking now is to upgrade to the 600mm f/4 and possibly buy the RF 100-500mm as a filler for the other ranges.