I tried sharpening on the final print, also some noise reduction in the 5D3 image to reduce the banding and noise in the deep shadows. The NR worked great but the sharpening helped only a little since it just could not make up for detail that was not there. The D800e wiped the floor with the Canon in that regard. On a small print it works well but large prints are brutal and show every single shortcoming. Given, I was looking at prints 20x30in and larger (because thats what I plan on exhibiting).
For smaller prints. Say 16x20 and smaller even 12MP is enough. 18-22MP is good up to 20x30in if all things are perfect with the best optics. Given Im looking at prints with my nose inches from the surface.