I have some concerns regarding keeping your tokens in an exchange:

1. If the exchange are not within the top 10 then its security is not as strong as fortress since it can be hacked.
2. Why would you risk putting it on exchange when you can keep it offline or in a cold storage?
3. Wallet hackers is just as notorious as Exchange phishers.

The list goes on but my point is it will always be better to keep your tokens offline until you want to sell them. Don't hold it on any exchanges since the listing can be retracted.