Well... other than the one incident noted above that was user error... this raid has been flawless. Still have about 1.25 TB left... partly because I switched over to jpegs instead off tiffs for most clients. I'm due to go in and clean out files I don't need anymore.... but that will have to wait a couple of weeks. 3.75 years and going strong! Still the same drives too.
For most people I'd recommend Crashplan.com over a networked backup. That's what I use.
I have Crashplan also... for the computers them selves... but not for work files that I need quick access to/ I have seen CP take foreverrrrr with some files.