Bounty programs are like freelance jobs you get. You have to participate in a good one to get some valuable coins. First thing you should check is project like will it be successful. Then check rewarding system and the bounty manager. If it looks solid and fair you can participate in it.
I agree with your opinion. Bounty mission is a good choice. There are some scams. Sometimes disappointment. It is worth taking a moment to choose a worthwhile project before starting a bounty assignment.