Can Forum be used by a membership and be completely secure?

Have posted about keeping BBPress user profiles private with the rest of the forum setup with the WPMU membership plugin. Have had no joy. The BBPress user profiles can be accessed if you have the direct url with user name.

I might be interested to replace BBPress with Forum if all of it can be secured with the membership plugin. Also, is there a feature that sends email to users when someone answers to their topic? And, can the forums be managed entirely inside 'pages' and integrated into the twentyeleven theme?

Asking this before I install, as I am getting tired of installing and uninstalling plugins that don't quite live up to expectations. Thanks.