The migration we have been struggling to get running is well under way now.
The source server is a single Xeon X5300 series Quad Core Dell with 15K RPM SAS drives and a Gigabit connection.
The destination server is a dual Xeon E5400 series Quad Core Dell with 15K RPM SAS drives and a Gigabit connection.
Both servers were plugged into a Gigabit switch with a large backbone.
The total time to move 57 mailboxes running close to 50GB was 3 Hours and 20 Minutes!
We did not experience any lost e-mails or anything left behind on the old server which would have meant a rerun of the Mailbox Move Wizard.
All in all, it is good to see that this critical portion of the migration has run through without a hitch. :)
Microsoft Small Business Specialists
Co-Author: SBS 2008 Blueprint Book