Upload & Sell: On
I own 7D, 5D III and 1D IV. 5D III is best of all three then 1D IV then 7D. 7D can do very well, but IMO, it is not as stable in a long burst ie will lose focus for no reason and then reacquire it and takes longer to acquire focus. I've only taken about 1000 shots on my 5D III, but so far it's been brilliant and I do a lot of bif shots. The 5D III builds on 7D's extensive AF options and the 61 pt give a lot of flexibility and the outer points are also really good.
For birding however, the 7D makes a lot of sense if you do not have any glass longer than 400mm. The 7D has effectively 1.45x the reach of the 5D III when FL limited and that's a huge advantage. It's why I didn't sell my 7D.
You can't really go wrong with 5D III and IQ is excellent especially noticeable at higher ISO's, not that 7D is too bad itself.