I had been with those exchange before, and I can say that before they are part of the good exchange we are having especially latoken which is an exchange that runs an ico that was when ICO was booming not now that it is scam. When IEO came into existence they still run some IEO which turns out to be failed project they lost their reputation that way same as p2pb2b and also vindax. You just have to be careful the way you transact with those exchange