I've been running a Linux software RAID1 on my boot partition and a RAID 5 array for root off of 3 30GB ATA drives. Worked great for ~4 months. While I was away on business (In Australia, no less, I live in the US) I kept getting an error message in my systems logs. I checked it out in /proc/mdstat and one of my drives was down. With one drive down the system ran for the better part of a month while I sat 7000 miles away. When I came back, I powered down the system, replaced the hard drive, booted it back up and synced the array. No problems. The system was a little slow while it ran on 2 drives, but I got no complaints from users. One of the great things about software raid, is that you can set up different RAID types and arrays from different partitions on the same set of drives. I run ext2 for boot and reiserfs for root. Love it and I'll continue to use it until something better and cheaper comes along.