While I haven't used BackupExec 12, I've had experience with 11, 10, a few other versions. I've always had issues doing restores with BackupExec, especially when I had a disaster.

As Gail mentioned, Backup Exec might work, and I hope it does for you, but I would not bet my job on it. I'd make regular full and log backups with SQL Server, or one of the non-agent based systems.