I would have to say go with SCSI. Either harddrive is good (they are both AV rated) but from experience, spend the extra dollars and get a good harddrive. In terms of necessary speed, make sure you have nothing less then a 7200 rpm, 8ms seek time, and a 33MB data transfer rate. Anything less would cause frame drops and other serious problems. I use a 9.1GB IBM Ultrastar, 10,000rpm, 5.3ms and it is fabulous. Go to www.onsale.com and save yourself a bundle on these harddrives.(posted 9219 days ago)