Just because a project is listed on exchange don't give them a check as a legit campaign, take a look at digitalbits, they are listed on exchange and doing absolutely great still refuse to be pay hunters reward,
To me that is not an authentic criteria to determine which campaign will be rewarding, there are so many disappointment from project owners that left hunters wondering and confused.
this is the reason why you need to make your own research before joining in bounty.
Listening to other suggestions will not work always so you need to make your own review for a project so every time you join a scam campaign no one is to be blame other than your self for not doing your homework.
Forget about research, lol! Research can only give 50% assurance about legitimacy of a project but still not enough to give a full guarantee that you will get your reward at the end of the bountycampaign, this is a question of the team keeping to their promise, if the team are not ready to pay when campaign is over, your research means nothing, because no matter how hard to try to research about a project, you can't determine what will is inside the mind of the project owners, that is one place your research will not work.