Bitmex is far more rewarding when it comes to one of the best feature they have which is margin trading but I think it’s quite too risky for newbie to deal with while Binance has less risk with their own margin trading and for the fact that they have the best competitive price in the market which is still the lowest for now as far as crypto market is concerned. So, I will advise most newbie first to try Binance before moving to Bitmex if the need arises.