So, if you have a D500 and you're thinking of buying a battery grip to go with it, you've probably already had to sit down and recover yourself. This thing is preposterously expensive. I went back and forth trying to justify what it was going to cost me and eventually decided to bite the bullet and get one. And I'm glad I did.
If you've had other Nikons and added a grip, you know what you're getting and what you're not. It adds the capability of an additional battery and allows you to have the same set of controls available when shooting in portrait mode. It does NOT add any additional fps. And as nice and roomy as the D500 is, I still like the camera better with the grip. I have medium-large hands and found that my pinkie was looking for a place to be on the camera before I bought the grip.
I will say, this is the 1st grip I've purchased that I didn't have to nitpick. Every other one from the D200, D7000 and D7200 had wiggle. And it drove me crazy. This one doesn't move. Once screwed on, it's solid with no flex whatsoever.
If you're on the fence on this, I will recommend it highly. At the time of writing, I don't remember what I paid for it so, the pain of purchase goes away quickly. I resented the purchase of all the others because they didn't make the camera and grip feel like one solid piece. This one does.
Hope this helps