Should I get 4 x 250gb hard drives in raid 0 or 2 x 500gb hard drives in raid 0. The 250gb option is cheaper but I only have 4 sata ports on my motherboard. Should I spend a little extra and buy 2 x 500gb? Or even 2x 250gb and 1 x 500gb? This is to be used in a whitebox virtualisation server..