Great example of this is Sliderocket.com (powered by a very complex Flash slide editor/interface), recently purchased by ClearSlide. My guess (with no inside knowledge whatsoever) is that SlideRocket was looking at an expensive tech transformation to move up to current standards and fix all the annoying technical debt they've accumulated along the way. (It's extensive: I'm a customer, their platform is buggy and dated.)
The design looks nice at first glance - but when I tried to figure out what you actually do, how you deliver on your promise, I was just confused. You're very features-first. Would love it if you started your copy and iconography with benefits and then talked about the features that support them.
I second this, http://chargify.com has many more features than Braintree, Spreedly, and Recurly. Also, they work with international merchant accounts/gateways.