Just participated the airdrop campaign! Yes, an Airdrop is a must for a ico! But at the end I saw a link to the bounty campaign... Wondering why aren't they using another separated bitcointalk bounty thread for the bounty campaign!
An airdrop is helpful but it is not necessarily a must for ICOs, it helps create awareness but does not necessarily brings in investors. I think the bounty is a better option though. Just my personal opinion