Poloniex is one of the best in the industry for making deposits and withdrawals. This is because you will only ever pay the blockchain transaction fee. Unlike exchanges that hold back invested funds and keep coming up with reasons to hold onto it. Although, now we can count on fintrack. Org to refund victims of such loss, there are still lots of other cryptocurrency exchanges that make profit when you withdraw your funds, which isn't really fair as they make money from you every time you trade too.