cos those are the best and 2nd best SSDs around, thats why.
Vertexes and XM25s will perform very good, and beat the living hell out of HDDs, but they cost alot, intel xm-25 80 gigs costs here around 200 euros.
I got 2x500gb WDs in raid0 and Atto disk benchmark gives lowest value (default settings) @ 0.5 around 50k write and 50k read, steadily increasing to 140k @ 2.0 and then rest of the test it varies around 150k and 160k both read and write (write mostly slight ahead).
I tested my samsung spinpoint f1 without raid and it gave maximum value of around 80-90k so i pretty much doubled my results by putting similiar disks to raid0, and small file transfer rate went up by giving stripe size 64k instead of 128k (lower for faster transfer rate and increase for big file transfers).
My intention was to give short judgement on raid 0 but it turned out to be "how raid 0 pwns".
but yeah you heard me, raid 0 is very nice but SSD will give advantage as it has no seek time and file sizes wont affect it's performance.
Oh, and if you want to benchmark your hard drives, atto disk benchmark can be found here: techPowerUp! :: Download ATTO Disk Benchmark v2.34
or google it.