Many bounty platforms are of high quality and professional at the present time such as bountyhive, bountyportals. However, with so many participants and the selection of quality campaigns is very necessary. Therefore, consider and monitor the full project before joining.
Yes, These are very good bounty platforms and have many participants. Of course, the project is listed a lot and you have to do the research before selecting the campaign that you join. I trust them. Because it is very clear and professional.