IBM's take on RAID: IDE vs. SCSI
Both AnandTech and TR had good things to say about IDE-RAID performance, so who needs SCSI?
Due to the lower cost, IDE RAID configurations are becoming more and more popular. However, cost should not be the only consideration when comparing SCSI to IDE in RAID configurations with 4 or less hard disk drives. SCSI offers a lot of advantages which save money in the long term. The following information describes the additional advantages of SCSI has over IDE in small RAID configurations.
IBM makes those Deskstar IDE hard drives that are being used in many IDE-RAID configurations, so this makes for intriguing reading
Separately, Storage Review has taken a look at the 3Ware Escalade 7400 card that has surfaced recently.
Update: Real World Technologies weighs the pros and cons of onboard vs. PCI RAID controllers.