We use InterServer to manage our client billing and collections for our commercial accounts. The interface is easy to use and the reporting is very helpful. We haven't run into any problems with the system. Our clients have been very happy with the service. We have not yet had any issues with the system. I would say that the customer service is very good. I would like to see more options for recurring billings. We have been able to automate our billing and collections process. We have been able to reduce the amount of time that it takes to process our invoices.