I have joined some of the bounty recently, I had collected some handsome amount of copytrack stakes which is my first ever bounty. However I haven't got any yet so still not sure do they really pay.
I found most of the bounty is hard to track and time-consuming process just to submit your work so I don't join all. I think they must adopt some easier process like phenom? I liked phenom's interface,for most of the bounty campaign like twitter,steem,facebook... they track your contribution automatically.