I have been using bountyhive for months now and it has never failed me. ICO's pays fast and gives fair payments. It also follows the schedule that the ICO has in its bounty page.
The fact is that basically there are practically no questions for the Bounty platforms, because they fully comply with the terms of the transaction. There are a lot of questions to the bounty companies themselves, who are often deceived by bounty hunters. Perhaps the time will come and you will have to create trade unions for bounty hunters to protect your rights.