if you are really paranoid, you could use macrium reflect to make images of the disk. get it to do grandfather / father /son or similar, and then use carbonite to back those up.
good thing about macrium is that it will email you on success / failure. workstaion version is about £50. v7 also has a crypto guard feature that allegedly only allows macrium to write over / to the backup destination. havent tried that bit yet, but you can just remove authenticated users and your own account from ntfs permissions of the backup disk, this'll further reduce the attack surface