I bought a D500 a little while ago and find this thread very helpful for tips and advice.
Looking to get a spare battery and have always found Duracell to be as good as Nikon on previous cameras. However looking at amazon reviews, some people do seem to have problems with them. Either they don't work or fail after a few months. The capacity of the Duracell is less at 1400mAh than the Nikon's 1900mAh. If anyone has both, do you notice any difference in the life between charges in the real world? How long have you had the Duracell batteries for? I would prefer to get Duracell if they are OK as they are less than half the price on the Nikon offering.