The possibility of data loss is one of my top fears. I'm glad everything is back on track. That stinks. About a decade or so ago, IBM drives died in large numbers because of a bug regarding the handling of Windows 98's shutdown process. I haven't bought their drives since.
IBM doesn't make hard drives, it's others like Toshiba. These weren't disc drives either, they were SSD's which were also failing.
IBM did make HDDs about 10-15 years ago. Nowadays they are making them with Hitachi as HGST. [EDIT] ''twas in 2002: https://www-03.ibm.com/press/us/en/pressrelease/380.wss Now they're somehow related to WD and Toshiba it seems ... Such oligopolistic...
I've seen a lot of suggestions here for Cloud Backup, I am surprised that no one has mentioned Backblaze. Looking at the array you've got 16TB there, while its probably a bit larger than they'd allow for a Home Account it still might be worth pinging them on it. Tapes will probably run you about $350 just in media alone to back up, a bit cheaper than spinny disks, but honestly not by a whole lot (4TB Drives are around 100 bucks these days). Of course none of this accounts for any type of redundancy. Have you thought about a distributed backup? Perhaps chunking into 1TB increments and distributing amongst the forum? Something like BitTorrent Sync? The problem is with your storage requirements Cloud isn't going to be terribly cheap, Amazon Glacier comes to mind, but its still pricey, at $0.01USD/GB you're looking at ~$10 a month for just a single TB of Storage, Microsoft's OneDrive that was mentioned earlier is probably the best deal, with Office 365 (which can be had for as little as 70 bucks) you get 5 accounts with 1TB of storage each. Amazon has the Unlimited Cloud Storage, but I really doubt they'd allow you to store 16TB (especially if you encrypted it which would be my recommendation).
What version of the RAID software are you using there? I have a similar looking software here for my storage server but it doesn't display disk serial numbers. I noticed that your software does show disk serial number.