But the unsatisfactory rating is based on just 1 unanswered complaint -- not exactly a major criticism (especially considering just how much there is to be critical about with Prosper).
Have you ever worked with the BBB? It's ridiculously easy to close a complaint. Just point to your catchall phrase in the TOS that basically says "tough cookies" for the victim, er I mean customer.
Or, if the customer actually has a legit beef, make him an unsatisfactory offer that you can convince the BBB rep (if you even have to deal with one) is reasonable.
Either way, the BBB will "Administratively Close" the issue and you avoid the stink of "unsatisfactory". Prosper blew this rating via simple negligence.
Prosper had 19 complaints and only two happy endings. That says a lot for a company of its size.