Which TC for D800 / 70-200 mm vrII
If you want to use a TC on the 70-200II I would pick the TC-14E(II). The 2x is a bit too much of a stretch for this lens IMO.
However you may also consider just cropping when you need to; the TC reduces contrast and the pixel-level quality is not as good as without a TC. Whether you find the resolution increase beneficial or not depends on what your aims are and also on the conditions (whether your lighting is high contrast or low contrast). Test.
My recommendation is that if you need to shoot at f/2.8 or f/4, use the lens without TC. If you can stop down to f/5.6 then the TC will most likely yield superior detail in the image.