When looking on bounty campaign period more than two or three months I will never join and checking again with distribution after six month later this the reason I am not interesting for joining, I am looking bounty campaign maximum running more than two months and distribution after bounty ended or payment have been sent on escrow. When getting bounty campaign have running long time period I will looking for other campaign where running short time and distribution soon after ICO ended. Many bounty campaign running very long time but the end just received little reward, maybe you ever joined with lyfe bounty campaign but received little reward payment after running more than three months.
There is another popular opinion - it is safe to join long running campaigns managed with a trusted manager. For example lets take a look on
bubbalex and
Ferrum Network bounty. Campaigns duration 3 months, distribution began in 3 months after the end and in 3 batches. In general, this campaign was from April to November. Everyone got what they earn, everyone was happy. So people should not be afraid of campaign with long running periods, but be selective.