Most reviews feature dedicated controllers (usually $300+). I don't have much of an idea about on-board controllers but from what little I remember, RAID-0 and RAID-1 are well supported on on-board devices and everything else (such as RAID-5) is a strict no because it eats up too many CPU cycles and degrades performance? (Forgive me for my very layman explanation)
If you have another boot drive (or another computer for your primary use), you could try experimenting with the two 500GB drives and give it a shot. If it sounds like too much trouble and you don't feel like doing a mini-review yourself, I don't think you would be missing anything.