Hi Lorraine,
in this case we aren’t using XtraDB Backup, we’re using mysqldump. We may use XtraDB Backup in the future, though I had the impression that the resulting backups are bigger because the ibdata1 file is copied, and that could be a problem for us.
We also plan to upgrade to 5.6 at some point, but we’re upgrading hardware at the moment and we didn’t want to change too much at once.
Chris