Results from the following lenses are now available in the Lens MTF Comparison Tool:
Canon EF 200mm f/2L IS USM Lens
Canon EF 200mm f/2.8L II USM Lens
Canon EF 300mm f/2.8L IS II USM Lens
Canon EF 300mm f/4L IS USM Lens
Canon EF 400mm f/2.8L IS II USM Lens
Nikon 200mm f/2G AF-S VR II Lens
Nikon 300mm f/2.8G AF-S VR II Lens
Sigma 120-300mm f/2.8 DG OS HSM Sports Lens
Note that variance charts are not available for the 300mm and higher focal length tests.