That's a fairly meaningless metric to go on. Every exchange that has been hacked (the majority of them) was "never hacked" at some point. You have absolutely no idea how good or otherwise Huobi's security systems and procedures are, so you are taking it on blind trust that they won't be hacked in the future.

Regardless, even if you decide you trust that their servers won't be hacked, you still have to worry about the security of your own account (phishing, hacks, malware, etc.), how your funds are going to be used (loans, trading, investments, etc.), if they will be safe while being used for those purposes (bad investments, bad trades, borrowers defaulting on payments, etc.), and all the other things which could happen to Huobi while your funds are on their exchange (scamming, shutting down, regulations, fines or penalties, excessive KYC, etc.).

It is a lot of risk to take for a small return.