webcam sites paying per minute / percentage
 

Anyone having experience with webcam affiliate programs paying per minute or a certain percentage of the customers purchase rather than a flat fee per sign up?
Considering that sites like ifriends pay now >$40 flat per new referred member, there must be some money in.
I only wonder if that's just an option for upsells from membership sites (where people have usually already proven to be willing to use their credit card) or if sending some general webcam traffic can generate a decent income as well.
In the last scenario, how many free membership sign ups are necessary to make, let's say, $1000 per month of them, or, how much traffic should be sent for a proper test?

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