Hi David,

Welcome to the forums. I use the 7D and 100-400 L combo. I agree it works really well. Sometimes the AF isn't as fast as I would like, but it is still much faster than my other telephoto lens (an old 75-300).

A few recent pics from the combination:


Loon-7326 by kayaker72, on Flickr


HB-7412 by kayaker72, on Flickr



small-8036 by kayaker72, on Flickr

Thanks,
Brant