If you want a fast one go Intel X25-M. If you want a slow and slightly cheaper one, go the Vertex.
IMO, the two dollars you spend extra on an Intel drive is more than worth it; as you would need several Vertex drives in RAID0 in order to reach the random I/O speeds the Intel offers you.
The sequential speeds (250MB/s - 70MB/s / 240MB/s - 145MB/s) are not important for the function of the system drive. What is important is the random I/O performance of the SSD.