Experience with billing systems

• Braintree (and to some extent, other lesser payment gateways)
  • Pros
    • You're in complete control of the billing system
    • You can do more complex payment setups
    • Widely supported for multiple programming languages; ActiveMerchant support
    • Some of the best support you'll ever see for e-commerce
  • Cons
    • You probably have to deal with PCI DSS security compliance
    • Potentially a lot of extra work (which may very well still be worth it)
• Google Checkout
  • Transaction Fee: 2.9% + $0.30
  • Pros
    • Very low transaction processing fees
    • Fantastic if you're already using Google for advertising
    • Google handles a lot of the messy stuff involved in billing, like chargebacks
    • There's now support for subscriptions (in beta though)
  • Cons
    • Google's API is different enough from other systems that you usually have to use a library specifically designed for Checkout (e.g., no ActiveMerchant support)
• Paypal
  • Transaction Fee: 2.9% + $0.30
  • Pros
    • Widely understood API; tons of stuff available for dealing with it
    • Essentially supported by everything
  • Cons
    • Lots of people are very vocal about not wanting to do business through PayPal due to bad experiences
  • Neutral
    • Tends to be popular with the young adult demographic who don't have credit cards and with eBay users
• Amazon FPS
  • Transaction Fee: 2.9% + $0.30, lower for bank accounts and balance transfers
  • Pros
    • Probably your best bet for micro-transactions
    • A good choice for payments for physical goods
  • Cons
    • I don't know enough about the system to say for sure