I have about six Batteries now for my D5300, 3 of them are definitely the real thing as they came with different camera bodies, the other 3 came from Ebay and I have no doubt they are probably fake as I never paid much more than £20 for each of them, bought them just over a year ago and so far had no problems but of course when you buy something which is snide/fake you do run the risk it might not work. So I would say you will probably be ok with them working fine and more than likely will have no problems but there is always the small chance they will not work or will not hold the charge, if you do buy from Ebay though then try and buy from a good seller and not someone overseas.