One of the big issue with high MP count sensors is diffraction, and with this camera diffraction begins at only f/5.6, many will say that it only begins there, but you really will notice the effect at f/11 and probably at f/8. Cameras like the 5D MkII begin diffraction at f/13.
The problem then is control of DoF, fine if you're using fast primes, but as a landscape camera? Well maybe then it's not the best choice to make
Yes but just to clarify for people who aren't familiar with the physics. Diffraction effects are caused by the lens, specifically the aperture (light bends when it passes an edge, creates bands through a slit, and rings through a small circular opening). The smaller the aperture the greater the effects of diffraction. The sensor itself does not cause any diffraction but as the resolution goes up for a given sensor size (smaller pixel pitch) the sensor will begin to resolve the diffraction effects and cause a softening of the image that offsets the increase in sharpness (and depth of field) that would otherwise be achieved by using the smaller aperture. Therefore, for a given sensor it can be stated at what aperture this effect begins to be noticeable.