For some reason, I have my faith on Bittrex.
But everyone is talking about coins and ICOs but I tend to believe most of the exchanges will be closed soon.
An exchange is a hell of a thing.
In fact, Bittrex is one of the trusted and good exchanger and once you said bittrex you will know all good cryptocurrency are there and all of them have good and high volume. As of now many people keep on creating good exchange so I do not have any idea which exchanger will last forever or which exchanger will be gone.