Agreed. Nothing worse than pulling a tape only to find out the backup was incomplete. It happened, it was painful, someone got fired for it. We check for errors

Agreed. Nothing worse than pulling a tape only to find out the backup was incomplete. It happened, it was painful, someone got fired for it. We check for errors while dumping databases, do md5sums after on the local machine and then again on remote server where the backups are synced. Most of our backups are restored on a daily basis on development systems so we are assured they work.