These traffic are really different. They are totally community building minded, and most of the time they are not enough legitimate for your Advertising networks.
It depend on the niche you market in. It works sometimes for CPS, but I don't know for CPA and others. You must test.
As far I've heard - works well for internet marketing fields (couple guys where promoting, also worked for male enhancement fields, however conversation rates were pretty low, and also you could try to hit AdSense)