You can do both easily. Airdrop is free coins without any efforts while bounties are earned through efforts...
so true. for those of you who like free stuff is Airdroplah answer. but do not expect more, because the tokens Airdrop provided are not too big.
Dont expect too much because its not enough to buy car but only cigarret.
Doing both is the best choice but if you have more time. If only small portion of time then go to bounty only.