Uh oh... I see Green Power HDD's. We used them for a while in big Raid configurations and their failure rate is bad.
Never again! We even had to stop using them as long term storage disks just in case... (though it appears heat was the main issue for them)
Back when I used desktop drives, I had several outages caused by a bad disk in a mirror. I log into the box and manually fail it out of the raid and we are good, but customers tend to get mad when their I/O hangs for hours on end.
It only takes one hung mirror in production, for me at least, to pay for a whole lot of 'enterprise' firmware drives.
http://www.t13.org/Documents/UploadedDocuments/docs2007/D169...
Until recently, you often needed a vendor-supplied MS-DOS executable to enable or modify ERC features on consumer drives, but smartmontools supports it as of v5.40, thanks to this guy:
http://www.csc.liv.ac.uk/~greg/projects/erc/
I just bought a 1.5TB Samsung HD154UI for $99 that supports ERC. There are reports that P-model variants of the WD 15EADS don't support TLER anymore, but I have several S- and R-model variants of that drive that do, including one that was manufactured in March; so it's still possible to get WD consumer drives that support TLER/ERC, you just have to be picky about the variant.