On Ebay I found High Quality Multi Power Battery Grip Holder Pack For Nikon D750 Vertical Camera for $78 and $10 for shipping from overseas. Here is the LINK
Most of the dials are duplicated onto the back.
The Sub-Menu dial is on front just like the camera and shutter release as well. Lightweight and I like because I prefer the vertical grip when shooting verticals and adding a little more balance to me for the lenses.
Everything works just great and that is all the pros I can think of right now.
Cons–Even after turning off the camera and the grip the battery will drain just sitting around in the grip.
The Nikon MB-16 is still available for pre-order. Here is that LINK. Price is $369. If you will be bothered by the battery draining then save your money and buy the Nikon MB-16.