Re: These boxes still scare me
What does RAID give you? it might save you from a single drive failure, that's all.
An accidential delete, theft, water, power surge and both mirrors are gone, but use an (additional) USB drive to backup the data, lock it away (pref in a fireproof box), or a second box on the network (in the garage/loft) that rsyncs overnight and (for less than the price of building your own dedicated NAS box) you have something far more robust.
Seriously, a single drive is (like you say) scary if your data is important, but having known a company that went under (pretty much because) they naively relied on RAID only to have the entire server and backup USB drives stolen, when 1Tb USB drives can be had for £50 and a fire resitant box for £30, just thinking RAID is all you'll ever need will disappoint when you could have had a cheaper and better solution, if you're going to do something to prevent loosing [:-)] your data don't do something half arsed.