We've got a client with a huge ($15,000) array of SSDs, that he's using to serve out about 9 gigabits of traffic per second from his webserver with one RAID enc

We've got a client with a huge ($15,000) array of SSDs, that he's using to serve out about 9 gigabits of traffic per second from his webserver with one RAID enclosure. Duplicating the performance with normal drives would be cheaper for drives, but take several more enclosures.