Use RAID for desktop computer?

If data loss is your concern, please remember that RAID is not backup. I suggest you invest in some form of backup, whether it's a 'cloud' solution or a simple rsync job to another computer.

This way, you can have your RAID 0 for performance as well.

Be aware that even if you are mirroring drives, the raid controller itself is a single point of failure.

It may be worth considering using an SSD as the OS/applications drive, for excellent performance (see Anandtech for a review of the latest Intel X25-M drive).

I opted for this, with two non-RAID HDDs for data (plus an external drive for backup), which works well.