SSDs live long enough. You get magnitudes more IOPS performance out of a single SSD than a RAID of 15k disks, it consumes magnitudes less power, it costs less,

SSDs live long enough. You get magnitudes more IOPS performance out of a single SSD than a RAID of 15k disks, it consumes magnitudes less power, it costs less, and it needs less maintenance. It's a complete no-brainer these days to put an SSD in your database server.