Last night after some updates on my media server, one of the disks in a mirror set failed a SMART check and was kicked out (fortunately I have good backups). It's failing on the bad sector count but I haven't done a deeper analysis yet.
However it's time to bite the bullet and do some upgrade work. I'm intending to replace all of the disks with larger ones to increase the storage size and when I do, use ZFS.
The box is based around a Gigabyte GA-880GM-USB3 mobo, with an AMD Phenom II X6 1055T cpu and buckets of RAM and the OS on a 240Gb SSD.