Here is the information:
Max Read: up to 525 MB/s (SATA 6Gbps); up to 280 MB/s (SATA 3Gbps)
Max Write: up to 500 MB/s (SATA 6Gbps); up to 260 MB/s (SATA 3Gbps)
It is not quite 50% but close in performance difference. You will still see the same performance with the Vertex 2 drives, so if the price is right... I say get it!!
Ok, thank you!