When choosing a lens for the Canon 5D Mark II camera you have to consider the look and feel that you are trying to create for the final visual product. My team and I have tested and played with these lenses quite a bit and here is what we have learned.
Canon lenses produce wonderful skin tones, have medium contrast and give you a wonderful gradation into the blacks. They are not stark and feel soft in comparison to Nikon or Zeiss. Canon lenses seem more colorful than all the other lenses available in the SLR format.
The focus pullers on your crew need to be aware of managing focus with this lens system due to the endless focus ring. That said, the image stabilization function on the 300mm, 600mm, 70-200mm zoom and the 100-400mm zoom is awesome. I have handheld 300mm shots with the image stabilizer beautifully. Do not use IS II because it moves the image in a way that does not feel organic and softens the image.
What is your experience with the Canon lenses? I would love to hear your comments and feedback from your shoot.