Well i don't participate it too many bounties because most of them are useless but when i do the first thing i do is check the amount of tokens sold and amount of bounty being given , most managers don't know shit and give out really high amounts only yahoo seems like a manager who gives fair bounty.
But back to the question if it is half of the total tokens sold forst thing is sell it right away because even if you don't other assholes will dump, after the dumping stop rebuy if you feel the project is worth otherwise cashout. I might sound like a asshole who crashes the price but unfortunately that is what happens always when bounties are given away.