I still pay for snooty, and the reason for that is that when a disk goes bad (not if; when) I pop its tray out, replace the disk, pop the tray with the disk back in, click a couple of widgets, and that’s it. I know it will be rebuilt properly.

(And I know I have to do that, because when the disk fails it beeps and lights a led near the bad disk)

It’s easy to build a NAS such as the one described in this article, but in the long run, data loss is significantly more likely.

Also, any guide like this that doesn’t guide you through “disk 3 failed, this is how you safely replace it” is imho incomplete, even if it doesn’t go through telling you how you know a disk has failed.