Fewth, as awesome and thorough as that article is, it made things more complicated lol.
If I feel I need better performance, can I always RAID my drives at a later date? Will I have to reformat them before I RAID them?
you can use onboard raid and yes you will have to wipe the drives are reformat.
for a 2drive raid o there is little performance difference from onboard and a high end card.
(assuming a newer motherboard)