There is no selection criteria in selecting a bounty campaign manager because all are good as campaign managers. Among all the campaign mangers, I think yahoo has got the highest trust level and he is prompt and perfect in managing campaigns like counting the posts, issuing the payments without delays etc. But I don't think he will accept to manage a bounty campaign. I think Irfan is accepting bounty campaigns. Just contact him and see.
yahoo has been doing bounty campaign, have participated in one and was done well. I just like irfan, mature and diligent, good communication and prompt. Yahoo is the most diligent have known, he barely goes offline.