3x128gb Crucial C300, it beats Intels and Vertex 2's/Sandforce stuff quite easily, on a sata 6 controller and enough bandwidth(we've yet to see at what speed newer sata 6 controllers max out, ICH10 doesn't go much beyond 500-600mb/s, A sata 6 SHOULD have more headroom, might need a very good hardware raid card to go with it.
THe crucial is unmatched in sequential reads and random reads, other drives get closer but can't beat the Crucial on writes, and its fairly competitive in price per GB to all but the Intel, though its noticeably faster.