Well, after issues with the MegaRaid SCSI RAID controller card (also rebranded by Dell as the PERC/2) under Linux (Red Hat 6.2) the company that hired me decided to go with a new card. One with better support, and known for stability. At first thought I'd choose an Adaptec, but I need to actually look around. It's got to be SCSI and be able to do RAID 5 with four drives. If anyone has any ideas or pointers, I'd love to hear them.
UPDATE: My mistake, it is to be RAID 1/0.