Hi! I am about to order a mac pro and I am planning to add another two 750GB internal drives (not from Apple) into it. Since I am using it mainly for video work, and according to Apple's site, it is recommended to add a RAID Card, but I am not sure if it is necessary. Currently I have 4 external HDDs attached via FW800, and they are not RAIDed and I have not experienced any problems for the past 2 years. So I am wondering if adding a RAID Card will make any difference? I appreciate any input. Thank you.