I purchased this service to integrate with my Amazon Seller Central login. It's a well-known fact that the Amazon seller metrics are....less than ideal. Manage By Stats shows me customers' names, addresses, email (encrypted) and all the data I need to follow up with them. I can run reports to find the customers who purchase more than once and a whole lot more that I haven't even learned yet. Mostly I use MBS for getting in touch with customers for customer service. Recently I signed up for the Email Append service which helps me to find their real email addresses so I can ask customers to join my mailing list.