Poloniex is one of the best exchanges to trade because the fee structure is very less when compared to Bittrex or Binance and they also has no ID verification upto limit of $2000 perday.So it is bet for small traders to trade anonymously.And almost all the coins are available in Poloniex so it is best in my opinion.
I say no to
POLONIEX very vulnerable to hacking, and support services that are very unreliable.
I would recommend Binance, because of the three exchangers you mentioned Binance is an exchanger that has the most number of coins and daily volume