And of particular importance to me was achieving a very low noise ISO6400 file that I was willing to use at A4 (which is kind of the max I print weddings at). The 6400 shots I've seen work incredibly well at A4.
In fact, they work so well I might even be willing to go to 12800. So far I've only been happy going to 3200... that's a pretty good win!
I don't know... my eyes tell me it's just a stop better than the 5dii but something about the quality of the noise makes me willing to go further.
When i tried the 5d mkiii i also noticed the same aspect of the noise being of better quality or easier to live with compared to the mkii, in addition to the better performance. So i would suspect to see the same of noise characteristic on the 1dx...cool!
1DX, 24mm f1.4L II, 35mm f1.4L, 50mm f1.2L, 85mm f1.2L II, 135mm f2L, 24-70mm f2.8L II, 70-200mm f2.8L IS II : D800, D4, and a whole bunch of Nikon lenses