I store customer billing info at SpreedlyCore, which also provides a provider-agnostic API for making charges/refunds against the stored credit cards. Right now my processors of choice are PayPal Pro and an "interchange-plus"-priced merchant account with Authorize.net as the gateway.
With SpreedlyCore, I can change payment providers overnight (to Stripe or Dwolla or whoever becomes flavor-of-the-month) without changing any code or having customers re-enter payment details. There's also no vendor lock-in to SC -- they'll hand off the stored billing info to you if you want to leave.
I'm also in the US, and most of my customer base is also international.