Get a RestoreTest server (a VM would be fine) and enough disk space to restore your biggest database (plus necessary overhead).

Then cycle through your servers, restoring the backups one at a time to your RestoreTest server. (You will need to harvest the necessary data on backups from msdb of each SQL Server.) The process:

1. Restore a database, report any errors.

2. Delete the restored database.

3. Repeat with the next database.

Also, don't just restore full and diff backups. Include your transaction log backups as well.

When you start doing this you will probably find more problems than you imagined would exist. But once these are all smoothed out, you will sleep better.

RLF