Okex is not large exchange nowadays, you should try it like binance, huobipro, or even kucoin and bibox is better than okex. I doubt the price can keep this level, hope the price will pump.
okex is not known in Europe and USA but in terms of volume, okex is in the top 5 exchange. Look here the ranking of the last 24 hours:
https://coinmarketcap.com/fr/exchanges/volume/24-hour/