They are not a scam exchange, people are still using it and can still withdraw money normally. But this exchange is not suitable for you to join IEO because most of the IEOs there have failed and do not have any successful projects and helped investors to get profits when investing.

No one will give you specific advice or recommendations on this matter. No one will want to take responsibility for possible problems that will subsequently come to you after acting on ChainX. Nevertheless, it is nevertheless necessary to take into account some facts that can characterize the exchange. ChainX is a centralized Korean exchange, which means it must be governed by certain laws of a particular state. In addition, the volume of trade indicated on coinmarketcap is 21 million dollars. After Binance is responsible for Coinmarketcap, I want to believe in the veracity of the indicators indicated on this resource.

There are series of IEO held there and lot of complained that they have been manipulating the result of their listed project. So for me, an obvious exchange like this would not progress, its like they are similar with other worthless platform such as latoken, vindax and p2pb2b exchange which proven to cheat or manipulating on their exchange.

Why you included Idex? That is a legit exchange and worth than these markets you mentioned.