sata raid 0 vs. sata raptor

looks like im gonna be building a new system, reusing a few parts. right now i have an 80 gig sata drive for windows along with 2 storage drives. im debating picking up another 80 gig to stripe with, or just running windows on a raptor. id prefer to spend under 150 bucks with this, so id rather not run two raptors in raid just yet. whats the better way to go?