In the event of a failure in your primary hard drive, you'd swap the drives and you're back up and running without a hiccup. The system puts demands on a PC's resources so you may experience slightly diminished performance. But it's a no brainer once it's installed. A non-SCSI machine can be given that functionality through the addition of an expansion card, which slots inside a computer. Competing with the Jaz drive is Castlewood 2.2 GB Orb drive.
Firewire models are also available.