Put My Sites navigation from admin Toolbar in regular menu

Hi,

I have multiple branches and 1 central site.
The entire multisite install is private for only logged in users.
When logged in I want all users to access the central site but branch access is restricted.

1. Do I need a membership plugin to control access? Would you suggest S2Members, Membership by Justin Tadlock or another plugin for a multisite?

2. I have added a menu for the central site. When users are on the central site I want a menu item My Branch that links them to the branch/branches that they are authorized to view. I will hide the toolbar on the front-end. So I want to add the My Sites (only I'll call it My Branches) from the WordPress toolbar to a standard menu. How can I do this?

Thanks for your support

~ Ruth