CEX.io has bad reputation in the cryptocurrency market and many people recommend to avoid it. Even if we will take into consideration that it is relatively old company (founded in 2013) and it is registered with FinCEN, at the moment we can see a lot of complains regarding impossibility to withdraw funds, unresponsiveness and fraudulent behavior. This exchange was attractive to many traders because of its unusual mechanism to process exchange orders, known as “fill-or-kill”. This mechanism allows users to sell and buy digital assets instantly, using current market price. If it is possible to perform a transaction with an agreed (or better) price in a period of time equal to 120 seconds, the order is fulfilled. If the price goes down – order is declined.