I do trading in Bittrex exchange and I will say, safe or not about trading platform, it depends on how we take care of important factors for our account, such as passwords and make sure you always use 2FA when you want to log in. With 2FA you can detect someone who will log in to your account, on average 2FA uses a message to your phone or your email. That's a way to keep your account safe which you have to do well, but for the security of an overall exchange I don't know about that.