Methods, systems and program products for replacing a master media file. Data indicates characteristics of a first user's multiple media files. At least one of the multiple media files matches content in a master media file. The content in the matching media file is of a second quality that is higher than the first quality of the master media file. A server system stores the matching media file in place of the master media file. The server system receives a request from a second user for content matching the master media file, and accesses quality parameters that indicate the second user can access a version of the content at a third quality that is less than the second quality. A media file that contains the requested content at the third quality is generated and sent to the second user.