Need KT7 Raid Hard Drive Advice

[ginky4]

I have a KT7 Raid Motherboard. I am debating on whether or not to go with 1 or 2 hard drives. IF i go to 2 i will use Raid 0. Will I notice any performance difference if I use only one on IDE 3 as opposed to using 1 on IDE 3 and IDE 4? IF I go with identical hard drives on IDE 3 and IDE 4 am I really going to pick up that much better performance? Has anybody here used one hard drive and then later added a second one? Did you notice any difference?