The only exchange i can actually trust is bitfinex and the reason why i say this is because of their customer support (which is very responsive) and how safe their platform is. They have all the features you will ever need for crypto trading (even more than what the average trader uses). The con, in my opinion, is that you need a 10k USD equity to trade which is too much for some people and that the platform is not available for US individuals. Other than that it's a great platform.