I've been using AC for about a year but have yet to try out any of the superbill and billing components. In the meantime my current billing company is not working out too well. Does anyone have a billing service/company that they use that integrates well with AC?

A could option is Office Ally.

We do billing and use EZClaim for 5 practices. Seems to integrate well.

Ditto EZClaim, with some middleware improvements.