Test remote Exchange 2007 SCR

We have a remote site for disaster recovery purposes.  I've got an Active Directory server with GC but no FSMO roles and an Exchange 2007 server running as a SCR target.  This setup is supposed to only be activated in the event of a full disaster.  The trick is how to test this configuration in a non-destructive manor.  By that I mean, not destroying FMSO masters because I've seized roles, destroying Exchange servers because they believe they're the master server for a storage group, loosing e-mails, etc.

If I create a test Storage group and a few test mail boxes on the SCR source and have these replicate through to the offsite SCR target.  If I break the link between the sites, will I be able to run the Exchange commands to update Active Directory for the Exchange mailboxes on the remaining AD box?  As this Active Directory server does not have any FSMO roles.  Looking at the FSMO roles, perhaps only the RID master may get used.  But as objects are being updated rather than created, it doesn't look like an issue to me, but I'm no AD expert.  Or are there any other problems with this appoach as it's not something I've tried before in a production environment?

My guess is when I reconnect the sites, the offsite AD server will update the onsite AD servers that the test storage group has moved.  After either forcing an AD replication or leaving it a while, I'll be able to remove the test storage group from the original Exchange SCR source.

Thanks for any help.