Depends on the airdrop of course, I've heard some of them don't even give the coins.
But if it's an actually good airdrop, then yeah go for it.
Yep, all projects (bounty or airdrop) are potentially good. But on the same manner, all are potentially bad.
So be extra careful in which project to participate and spend time on.
Lately I have joined in two (2) airdrops and they are managed by trustworthy and proven managers backed by excellent dev team.
And I find it worthwhile and beneficial at the same time. It was a wise decision to join in those projects.