I promote casinos directly and through my own sites.
When I promote a casino directly through a PPC engine, I generally see between a 0.5% and 1% conversion rate of 1st deposits vs. hits. Varies widely based on the keywords, and it varies widely based on which casino I’m promoting.
I have experienced casinos outbidding me on keywords, but I’m not surprised at that.
I agree with BB1 though, and if I ever get to a point where I have a high level of confidence in my websites, I’ll start moving more in the direction of sending traffic only to my own portals.