Sorry, I revised the question -- I'm basically asking, what you'd pay on top of the premium. To boil it down, I want to know what you are willing to pay to acquire a random user.
You have to ask yourself if you really think that you can convert any of these users. There is a world of difference between targeted and untargeted traffic. You probably wouldn't even get any usable metrics out of the deal.
You are also talking about an investment of 2 bucks per user, and you could almost do better with a basic cpc campaign. You'd end up spending a bit more, but you be much more targeted.