C'mon! NOBODY is going to chime in with "Sell the body and take the golden opportunity to switch to a Nikon system"? The trolls must be out enjoying the nice weather or something.
Well, it has happened. Though not from a troll, i guess?.
Sell the 5D2, especially if it's one of the banding-prone early models.
buy a refurb D800 and a new Tamron 24-70mm f/2.8 VC and have more fun w immensely better IQ.
Though if a 5dII is all he has, this would be a good time to move if considering Nikon. If i wasnt already invested in so many Canon mount lenses, I might try the Nikon d800e. Or if I was rich. If I was rich, I would still keep all my Canon gear though. Besides, I am thinking there is a good chance of Canon releasing higher mp, better sensors in the next year or two. Not psychic, just an uneducated guess. Nothing personal Aglet. I have been very impressed with the D800 images, and as you can see, i own other brands of lenses. But am still very satisfied with my Canon gear, and still a fan (not "fanboy"). Come on powerball!