It's really difficult to find a reliable one nowadays, unlike before, even if it is a scammy it will be listed on the exchanges on the next day. I followed some bounty managers who have a good credibility and extensive research to avoid promoting a project that is a fraud from the very beginning.
Exactly. Known reliable bounty managers is a start to get good bounty programs that really pay. If you are following one or two managers, that is more than enough. If you are a risk taker, you can try those unknown developers that are doing their own bounty programs. But for me, if you choose the right manager, then, you are at peace that you are in good hands no matter what.