IMO the D810 is the finest digital camera that Nikon has produced to-date. The combination of high resolution and high dynamic range of the sensor, elimination of the anti-alias filter, and the various features of the pro body make it a pure pleasure to work with.
The detail that this thing is capable of is astonishing. I wish my skills matched its capabilities on more than random occasions. Below is an example of the possibilities.
Nikon D810/Nikkor 500mm f4
1/1250s, f6.3, ISO200
Full frame (very slight crop due to straightening)
Full rez w/no sharpening applied other than the LR default export sharpen for web.