• I'm not talking from first hand experience, but it looks like it should be fine:

    http://msdn.microsoft.com/en-GB/library/ms191304(v=sql.90).aspx

    Optionally, specify:

    - The INIT clause to overwrite the backup media, and write the backup as the first file on the backup media. If no existing media header exists, one is automatically written.

    Also, when you first start this sequence of backups going, there would not be anything to overwrite, so surely it would not break just because it doesn't have anything to overwrite now?