I MFA'd my 70-200 f4 + 1.4xii combo about 2 years ago. I never really used the combo because I purchased a 400mm for BIF. Last year I sold the 400 and stopped shooting birds.
Last month I decided that I wanted to start shooting birds again and since the combo above is all the reach I currently have that's what I'm going to need to use for now.
So for the last several weekends I've been wandering around the yard trying to find a bird to shoot to see how well the MFA is on the lens. But unfortunately there were none around. Today I went to a nearby marsh (beyond a local shopping area) and as soon as I got there an eagle flew away and I was left with nothing to shoot. After waiting around for a while the eagle didn't come back so I gave up and started driving behind the shops to get back to the road. And then I saw it. Two perched birds just waiting to be photographed..... a crow and seagull eating out of a dumpster and unconcerned that I drove up to them in the car. 
The MFA seems to be good and the 70-200 f4 + 1.4xii is really sharp!
