There too many bounties nowadays but ofcourse it is up to you which of them you really actually participate. First things first is by checking their projects if it has a good future.The team is very important if they are always active through their social. media. Telegram community is one of the one big impact if they have big community. If they have a working product and their icos become successful.So far there are many bounties that is Legit but you need to do your own research first.