Is there any rating of bounty managers available? That could be a great resource to see who is most experienced and best.
I've never heard of such ratings but I've made my personal (mostly subjective) evaluation of the managers for the bounties I participated in.
For example, I know that bounty manager XXX never provides spreadsheets, so I wouldn't participate in any of his campaigns because in this way I am not able control my work.
And on the other hand I know that bounty manager YYY is always available and helpful - so it is a real pleasure to participate in the campaigns that are managed by him.