i had a closer look at the D600 autofocus... as good as it looks on paper i think it´s not that the 6D is much worse.
sure the D600 has more AF points but they are so cramped together that 66% are useless.
i could not test sport or action and how good the D600 is at tracking moving objects.
based at??? your own tests
I don't even see why these camera's are being compared. The 5D3 is equal or better in every way except in DR. Especially the AF, which just makes any nikon camera cry and weep in the corner.