Gcox is a trading platform pretty similar to most of the already existing exchanges. All its features are not original but just recycled by the team. It was released just to be considered as another option of trading, especially when the great of the markets are facing great order of sales and make it impossible to trade rapidly.
In short lines, this exchange works properly and offers customers a set of options to get what they want while trading. It supports different tokens, and although it is quite limited, the representation is still good. It is possible to find liquidity in this platform.
Now, from a general perspective, this services is not as good as advanced investors might think. They already confirmed it just works for small orders, and the earnings can be too small.
I might recommend it, and I suggest having it there just as an option. But if you want to receive incomes, then keep trading in your common platforms. You'll get more by using the frequent official pages.