if those high ISO samples are true , then D800 is the clear winner. it performs same as D700 with 3X resolution.. even at ISO 25600 can be used with noise reduction and re sampling.. i dont think 5DX will compete against D800.
People are going to do the same test as D700 Vs 5DII by re sampling to match .. i dont think 5DX will stand...for 3500$ definitely not worth buying 5DX compared to D800. wht you guys think?.
The camera isn't even announced yet, no rumors or specs about high ISO noise and you already say it can't compete