program owners ccbill or epoch
 

which do you use and why?

paycom - way more flexibility and customizability (is that a word?)

Yes, "that" is a word.

If you have to choose from 3rd party processors, cascade with whoever scrubs the least that day. It's never good to have 1 set at all times.

The ideal solution however, is a merchant account.

ccbill, for affiliates sake.