I had one of my not-so-trusty-it-seems Maxtor 20GB drives from my RAID 0 array go down on me. I RMA'd the faulty drive, but the new drive will be a totally different spec, (ATA 133, different seek time etc.) so to keep get my RAID 0 working like it should, I picked up a couple of 40GB WDATA100 8MB cache drives.
My drive index in SiSoft Sandra is up 33% above what it was with my Maxtor drives, so I'm pretty happy with that.