Also with the 1.4 tele-converter. The pics are shaaaarp. No need to buy the new one.
The AF on the 7D is painfully slow for some reason. And hunts more than the old lens. It seems to me anyway. But, it is to soon to really draw a conclusion yet. I will use it for a few months and then decide what problems, if any exist.
So far, a good light weight birding lens. Definitely sharper than the old IS version.
When I get back to the ocean and start shooting raptors and water birds, I will be able to tell how good or bad it is.