This is more of a tour of the past six years or so of various iterations of Fenimore backup solutions.

• Solution 1.  Soon after I got married I found that between my wife and I we had around 1TB of movies, images, and documents from school.  We were also accruing around 5-10GB a week on family videos and pictures (hey, 1080p video cameras are readily available, and generate fairly big, hi-res videos).   Around Oct 2010 the price of 1.5TB drives was pretty low – around $80 each (this was right before the huge price spike a year or so later due to some disaster in the Pacific).  So I built a 3TB software-RAID 6 array with linux and a large tower.  I also had two 3TB RAID 5 arrays that plugged into hot-swap bays.  I periodically rotated these arrays to an offsite location.  By “periodically,” I mean it was every week or so for a month, then exponentially decayed to about once or twice a year towards the end.  
• Solution 2. Enter the QNAP.  By this point I had upgraded to 3TB drives in my consolidated linux solution.  I took those drives out of my linux box and moved them into a 4-bay QNAP (TS-453 Pro).  I found that all of these 3TB WD Green drives started dying.  As I write this I am actually not sure what the heck happened, but soon I found myself buying some 5TB WD RED (NAS-grade) drives to replace the WD Greens.  These have worked much better.  This solution has also been nice because anytime I need to do work on my linux box or on the NAS it doesn’t take down my whole network.  It was also nice because I ended up making all my files accessible (in theory) via QNAPs cloud software.  The only flaw is that I tried to continue my offsite backup scheme wherein a drive was cycled to an offsite location; this actually was worse with QNAP, because QNAP doesn’t like the drives to be removed. 
• Solution 3: Redundant QNAPs over VPN.  This is basically an upgrade to my QNAP solution where I bought a cheaper 2-bay QNAP.  The second QNAP fulfills my offsite backup goals. It sits on the other side of the country and is available 24/7 for my main qnap to push a copy of my data to it.

Overall I’d say this solution is just about flawless.  It at least seems secure, works well, etc.  I found, for example, I could get to my files when I am not home.  I was even able to stream video from my qnap via PLEX to my laptop in my hotel; this turned out to be useful, for example, when my daughter wanted to watch tangled, which worked fairly well.