Fixed bounty is fair for all participant, but as i know many bounty with fixed allocation is not pay hunter higher than stakes based bounty.
that's why even i'm prefer to participate in stakes based bounty than fixed allocation
Its been a long time since the last time i join in bounty? About the fixed terms its too obvious that this one is securing allocated payment in that way they cannot use all for bounties not even get 0.5 % of total supply to pay for participants. Only the owner / dveloper can only be benefited with the fixed rate.