Just from what I have seen so far, I would not trade my 5D3 for it for image quality. The 1DIV and 5D3 both have it beat at 6400 anyway.
The AF and FPS are the main reasons I went for it. One thing I will say is that it does NOT seem to have the same blue channel noise problem at low ISO that the original did, or at least not in my very small test so far. I will be going out momentarily for the customary new camera moon shot with it
