Haven't heard the name kucoin till now, looks pretty now but as binance is having good trading volume lately.
I am still using bittrex and hoping they will not just suspend me like they have done to thousands of bittrex accounts.
Polo is still struggling to resolve all support tickets....
I don't take any chances.
I moved all my coins/tokens from Bittrex and Polo to Kucoin, Binance & Liqui.