"The JPEG engine is so good I really doubt there would be any point in using the RAW option at low ISOs unless youre a pro shooting on assignment with strict orders.
I can't imagine anyone saying that about any Canon, as much as I like Canon cameras and would kill for the 1Dx
Interesting whilst I mainly shoot raw I have never had an issue with JPG white balance on my camera even in AWB. With regards to the later cameras some reviews for JPG performance for the 5D Mark III are saying the JPG performance on that camera is very good. I would expect the 1DX to be just as good in this regard.
In the video below they compare JPG of 5D Mark III to D800 and Canon performs very well.
Canon 5D Mark III vs. Nikon D800 Part 2 with Mike Drew - YouTube