Cache plugin will display same (cached) HTML to users who are not logged in. And, basically it does not recognize anonymous user based on IP (cookie). Therefore, features for anonymous user will be severely limited. For example, Q2A allow anonymous posting by default. And, anonymous user can edit / close / hide own content. In this plugin, anonymous user can post. But, he can not edit / close / hide own post. Users do not like this specification would not use my plugin. If your plugin required login, it might work correctly. Vice versa, if your plugin do not require login, it might not work correctly. In other words, both plugins will not be compatible. This plugin is very powerful, but do not forget that it is a limited functionality.