70-200 F4 IS vs 70-200 F2.8 IS II

Tried finding a thread on this comparison but found non. So for those of you who have shot both, or a couple of version of them, what are your thoughts on them. Is the 2.8IS II worth the extra upgrade or is the F4 IS good enough if you dont require 2.8. Thoughts, opinions, and jokes welcomed

If you don't need 2.8 than get the 4 IS.

I owned both at the same time and the 2.8 is as sharp at 2.8 as the 4 is at 4. They are even at f4 as well.

I sold my 4 IS because I couldn't justify keeping both and needed the 2.8 for concerts and weddings. The 4 is a great portrait lens.