Last year we had a full test of our disaster recovery plan (always comforting to be part of a company that has one). Mostly went well except that the disk segment replication to our DR site ended up with unsync'd filegroups for our primary db server so we couldn't do the restore, meaning a complete failure in the end.

If it was a real disaster, we would have had to resort to tape backups taking our DR recovery from 3 hours to over 48 hours, and having some data loss.

Always good to make sure a restore works.