If you are ready to disable PST file use the settings can be applied to Outlook 2007 with Group Policy using the Office 2007 Group Policy Administrative Templates.
In part, controls what users can and cannot do on a computer system: for example, to enforce a password complexity policy that prevents users from choosing an overly simple password, to allow or prevent unidentified users from remote computers to connect to a network share, to block access to the or to restrict access to certain folders.
Intelli Mirror technologies relate to the management of disconnected machines or roaming users and include roaming user profiles, folder redirection, and offline files.
To accomplish the goal of central management of a group of computers, machines should receive and enforce GPOs.
Outlook PST files are a problem for Exchange users, and give no benefits over Exchange mailboxes.
You have to use them on a local drive, they are difficult to back up, and tricky for the administrator to manage.
In any Exchange environment it is probably worth considering implementing a server-side archiving solution before disabling PST files.