I have a 13" Mid-2009 MBP 2.54ghz Core 2 Duo, with 8gb 1066 ram...this thing has been a tank. Currently I have a 250gb Samsung 840 SSD in the HDD slot and a 500gb 7200rpm HDD in the optical drive spot. Right now I keep the OS, Apps, and projects I am working on on the SSD. I keep media such as pics, vids, and music on the HDD. I just read a write up on how to setup a fusion drive on this machine and combining everything onto one logical drive would be a little more convenient...I guess. I have a few questions though. Is this worth doing? Will this make the OS/Apps run slower? If one disc fails, do I lose everything like a Raid 0 array? Pros? Cons?