@jin I get it now... the light bulb went on. I kept looking at this from where I'm at now, not where I will be media data-wise. I'm really nowhere near needing a RAID. I have just over 1tb or so of music... That gets backed up to an external drive that goes in the safe. On a 3TB drive, you should be able to conservatively fit about 150 or so blu-rays assuming a combination of largely un-further-compressed MKVs with all the BS stripped out of the movie (15-20 gigs on average) and some other non-critical stuff compressed down to 2-5 gigs. I'm at 40 blu-rays. I have way to go, though I will be ramping up the buying once this built.
So I now see where you guys are coming from. Assuming at some point I have 3 HD's full of movies, for the cost of an extra HD, if one goes down, it's a non-event other than buying a new replacement drive... which I'd have to do anyway.
i think I was getting confused also with NAS. A NAS is just a sharable data store on your network... which can be a RAID or not. NAS makes sense near term, RAID makes sense a bit further down the road.