Canon EF500mm f/4L IS II USM and EF600mm f/4L IS II USM review – Giants in the rangeBy David Newton - Monday May 27 2013 Lens Review
Both of these lenses offer exceptional performance that far exceeds anything else available in a Canon mount. They are also built to last, with fantastic build quality. If you’re looking for the best, these should be at the top of your list. The only things to keep in mind is that they are both heavy lenses - though much lighter than their predecessors and not unduly heavy for a lens of this focal length and aperture – and they are also expensive, but the best usually is.