I'm a mod on another forum that uses this concept. It's used with a good deal of success. I will say thought that deals that require an initial deposit are typically the ones that aren't utilized as often. One because most players are not willing to deposit and risk their own money, or because they live in the US and depositing is too difficult. Usually it's a combination of the two especially with so many rooms changing policy and not allowing players from the US.

Once the CPA is reached, do you continuously earn PO pts based on rake as well?