I think Bounty is more effective. After entering the 2018, I did not see any valuable airdrop projects. Many projects do not have airdrop to attract people's attention and achieve the purpose of publicity. Now the ETH gas fee is relatively high, many projects may consider that the cost will not give you tokens.
Thats rights some other tokens given by airdrops don't have any value on market also eth gas is high that the value of token in sold will be equivalent only for gas so means useless. But if steak on bounty hunting and search for the better one it has a bigger chance to earn more tokens and bigger value also when hold some other time. The thing is that be patience on bounty because some ico woul take couple of months and others maybe years.