The days of Bittrex and Polo are long gone.
Binanace and Kucoin are good enough even without verification if you are not withdrawing large at once.
And the success of these have influenced many newer exchanges like Viabtc's Coinex.
I tried to find the owner of Kucoin and some videos on the team behind it there a shadow company you will probable get robbed like I did .
They gave my funds or took my funds either way I lost money on Kucoin .. I used all the security measures its easy to verfy that I did and I had nobody login to my email to confirm the withdralws I have the ip logs for that too.
I have contacted Kucoin and they have not replies at all .
If you put money on Kusoin maybe you will lucky and not get robbed I have no Idea.
I have had money on BLeutrade fro years lol little bitty exchange with half the security and its was still there put money on Kucoin and get robbed in a matter of days .
Kucoin is like Cryptsy or Mt. Gox.