a few question regarding D4 and D800 IQ and features

You are indeed right but my comments differ in an important way.

On photography blog I gave what I realize was an uneducated guess and observation. Skin tones and white balance are to my eyes (the eyes of a man that has been calibrating projectors, mixers and cameras for live event for years) exceptionnaly good on the Fuji. ISO performance also seem better on the X-Pro1. I assumed these were the main reason one would pick a camera over another, plus or minus a few other features.

However writting that comment got me thinking; I do not choose my projectors according to IQ alone (as explained in one of my reply in this thread) surely professional photographers do the same thing. So I though about comming on this forums as ask the question to pros using pro equipment, what features, other than IQ, are you guys looking for in a product. So far I had good answers; fast file transfer, huge buffer, dual memory card slot, lens selection and avillability (although that point seems challenged by the fact there are already at least 7 different type of adapters including Nikon adapters for the X-Pro1 and many mft cameras but that is not the point), reliability, solidity, predictability, very fast very accurate AF...

So same premise different objectives.