We use Chargify to handle all of the recurring credit card payments for our business. We previously used another service for recurring charges, but required a higher level of support and customer service, which Chargify was able to provide along with a robust product with a solid API.
We previously used another recurring processor. Although their product worked well and was much cheaper, their customer service became increasingly less responsive. Chargify's API is equally easy to implement as our previous recurring payment processor..