The worst experience about the exchange I got on IDAX and COSS, my assets were lost on IDAX because the developer ran away with all the customer assets. Meanwhile, my experience at COSS exchange is that after shutting down the service, suddenly my account cannot be accessed. So I hope you never keep your assets on the exchange for long, because we don't know what they will do with our assets in the future.
both of them really suck for me, but i dont have any assets there. Saving unreputable exchanges really make us worry if someday they stop operation and without any notification hold our crypto assets. Especially coss, since its launched i know its only fake exchanges that will rob our assets.