When the Electroneum was conducting a bounty campaign, many at some point thought they were scammers and left the campaign - lucky ones who stayed in it and got a good payment!
When i was starting here in cryptocurrency a lot of people in my country is promoting electroneum and i am confident that it is not a scam, electroneum have raised a lot of money on there ico and even i dont invent on it, i know it is not a scam.