Computer upgrade/ backup for MAC

[sk66]

So i just upgraded my MacBook Pro to dual 1TB drives in a RAID 1 scheme. Works very well.
Initially I had trouble setting the RAID scheme up as I didn't realize the drives to be used in RAID had to be blank in order to set it up initially. While doing a bit of research to resolve my issues I found out that it is possible to set up a MAC's single internal drive in a RAID1 configuration with an external drive.
This could be very useful. It does an automatic complete backup of your internal HD every time you plug in the external, and without using any other software. The backup is also "hot swappable". If the internal drive should crap out, just plug in the external and the computer will automatically boot/run from the external.

HERE"S THE LINK if anyone is interested.