both have advantages and disadvantages for each. if you want for instant coin you can choose airdrop. but bounty is better than airdrop, you can get make more money from bounty, though bounty need to take a long time till end of ICO.
Both have but one is the most greatest and that one is the bounty camp as you said since this selection is paying more money rather than airdrops but it's time and effort consuming, but if people could participate on both then they should do it since as you said there are ICO who end up so far and sometimes they will announce an extention and airdrop coins will be one of hunger stopper since those coins can be sell which can be use by us on good basis.