I just started with this so maybe it turns out I'm completely wrong here... but what I looked for was the following:
*Good project idea
*Enough people intrested in the project
*Good team
*Good bounty manager
*Enough funds distrubuted to bounty hunters
So basicly the same stuff I look for in an ICO except for the bounty part.
I also take my time to look out for all these when I am looking for a good signature campaign to join because I believe these are some of the important things to note before joining the group for you nt to end up in a scam project.