I'm a firm believer in backups. With such a wide selection of inexpensive hard drives, there's no reason anyone should have to play binary Russian Roulette with their precious stuff.
My RAID0 drive array has an 80Gb "system" C:\ partition, and a 220Gb "storage" D:\ partition. Since Windows "Restore" is inherantly unreliable, the 220Gb D:\ "storage" partition provides space for DVD's, and has a "backup" folder created by Norton Ghost 03 containing image files of the C:\ partition.
However, images can be corrupted by "internet schmegma" (virus), hardware failure (drive crash), and you can't boot up your system to an image. Therefore, the Seagate 160Gb "backup" drive exists for only one purpose; Norton Ghost 03 is used on this drive via a boot disk, to "clone" the RAID0 C:\ "system" partition. The "backup" drive in my sig has two 80Gb "clone" partitions, and is on a separate controller, which is disabled in BIOS.
The only three situations when I enable the drive controller in BIOS are; performing a clone, retrieving files mistakenly deleted, or restoring the C:\ "system" partition due to corruption, such as the inevitable SW install from hell. In the event of SW problems, the "backup" drive can be booted instead of the RAID0 set, which will allow you to continue working.
Cloning is the fastest possible method of creating discrete backups, and unlike RAID1 mirroring, the backup drive is not operating concurrently in Windows with the RAID0 set, so it remains diabled, as secure as a tape on the shelf, imune to corruption, and therefore, 100% reliable. The only catch is that you must clone at appropriately regular intervals.
Hope this helps. Enjoy