Use either and cascade to the other.
When you offer affiliates to join either they go for CCBILL most times. Maybe because they are already with CCBILL.
The good thing about both of them is THEY PAY THE AFFILIATES and do it with one check for all the sponsors. Which is a bonus for both the sponsor and affiliate.
The affiliates know they don't have to trust you to pay, reach a minimum level, wait for you to pay, the check won't bounce, it could get cleared faster at their bank because it turns up every month (does not apply to wire transfers) and lump all their payments together.
None of the third party solutions do this and if you don't do the payments yourself you will need to cost in another company doing it for you.
Both admins are good and take a bit of time to get used to. I would put CCBILL ahead of Epoch because I can phone and talk to guys who really know their stuff and their site. More so than Epoch. I can also do more on CCBILL like join prices/length and on Epoch need to send them the prices/length for them to give me a link (unless they changed it recently).
It takes a bit of time to fathom their admin areas out, but should not be too hard if you're running a site.
Epoch scrub less. I know this from the content stores on sales a little above $29.99.
