I had previously used nBill to try and deliver an online membership renewal system for our club. Unfortunately, I wasted hours of work trying to import our membership database and create custom fields to match with nBill. Got a long way down the track to discover the source code was encoded. Doh! The main requirement I had was to have a payment system integrate with Community Builder. Coming across Payment Form has been a revelation.
Tuan helped me customize the component so we could create custom fields as required and got the CB integration working smoothly. All in all, a great component backed by great customer service.