From what I read, they don't pay out if you supply the traffic.
As for using them as a PPC, DO NOT! About 3-4 days ago, I decided to get my $110.00 balance refunded back into my account. They NEVER answer their phones (they have once, out of 5+ attempts). After the person I did speak with said they would send this request over to accounting, I was sent an email yesterday saying that they cannot refund any balance and that it must be used. Such BS. I'm contemplating doing a R10 through my bank (chargeback).
So if anyone is contemplating using them as a network to advertise, take my advice and don't.