Yeah I'm a fan of RAID 1 for that reason. I'll take the slightly lower performance (because the write access time is the worse of both drives, and having to disable the write cache), in exchange for the increased data security, any day.
If you get one of those $300-$400 RAID cards, you can actually get hugely increased performance even with data security: On a RAID-5 array (or other configuration), there is a large (128MB or 256MB) write cache on the RAID controller, backed up with a battery on the card. The battery holds the memory for 72 hours in case of power loss. What this means? All writes are "instantaneous" because the controller reports the write as complete the moment it hits the cache.
The downside? You have to test the battery periodically, and if the battery backup fails because you wait too long to power up the computer after a power loss, or just for any other reason after a power loss, your file system and/or data is now corrupted. So I decided just to stick with regular RAID 1.