> RAID is a waste of your goddamned time and money.

Backups are important, since they protect against most problems, whereas RAID only protects you from exactly one thing:

On RAID, when one disk has a hardware failure, the system keeps on running. In many cases, if you take appropriate precautions, you might even be spared a reboot when you unplug the failed disk and plug in a new, working disk. Otherwise you’ll simply have to shut down, quickly unplug the failed disk, plug in the new, working disk, start up and it’s all good again. You can even put off this downtime to a later, more appropriate time of the day. When the new disk is in the machine, the sync to the new disk can be done while the system is running, and the only system downtime is for physically exchanging the disks.

Without RAID, the hardware failure means that you:

1. Lose all files and changes since your last backup, and

2. Have significant downtime while you restore from your last backup. If done over the network, this could take a very long time, but even if restoring from local disk, copying takes a lot of time. While copying, your system is down.

Whether this means that RAID is a waste of your time and money depends on your personal tolerance of points 1 and 2.