I do some video editing sometimes. I tried to archive one of my projects to Blu-Ray (all of the clips, video files, etc. etc.). Storing 300GB in 6 different BluRays means 6-points of failure.

And more importantly, BluRays have a 20MB/s read/write speed. Modern Hard Drives read/write at roughly 200MB/s.

A 5TB Hard Drive is just far more convenient, faster, and reliable than stacks-and-stacks of BluRays. A BluRay is great for the "50GB of important data" (Tax returns, resume, other important documents).

Having one 50GB "highly reliable" source of storage is great. You can clone that one disk, leave some at your parent's house / some other house you trust, have 3x disks for redundancy at home, etc. etc. Its the easiest way to achieve high-reliability.

Oh, and leave a copy in your 5TB Hard Drives too, for convenience sake. But BluRays are cheap for copies and long-term reliability. But they're otherwise awful to work with in my experience.

BR has 100 and 128 GB sizes now, which I use, but doesn't change your calculations much.

LTO-7 tapes in the 6/15TB range are between $60 and $80. LTO-8 tapes in the 12/30TB range are about $199 though seem largely on back-order. Double-capacity (24/60TB) LTO-9 tapes are planned.

But tape drives are $2000+.

Which means you need to store over 30TB to 50TB of information before tape drives are more cost effective. I've always wanted to make a tape-drive computer, but each time I run the costs... its just completely unfathomable that I'd ever store the amount of info needed for it to be cost-effective.

If I were to build a big storage device for my house today, it'd be Nas4Free system with 6TB Hard drives (avoid shingled drives, PMR for cost-effectiveness, Helium is unnecessary if you stay below 8TB). 6x 6TB Hard Drives with RAIDZ2(similar to RAID6) for a total capacity of 24TB of storage / 2x parity drives for resiliency.

That's only $160 per 6TB hard drive (https://www.newegg.com/Product/Product.aspx?item=N82E1682214...), so that's probably going to be cheaper than any tape-drive based system you can build out.

Sorry, I wasn't recommending tapes, I was just providing the $/GB as requested by the parent as a point of reference because I had no idea what it was until I looked it up. I figured it'd be interesting to others too.

Plus you need to physically manage the tapes, it is hard work. The alternative being to provision a bunch of hard drives in a NAS and from there it is all software/automated (up to a certain capacity).

Tape drives aren't exactly fast either.

Random access times aren't great -- to say the least! However, raw bandwidth isn't bad, LTO-7 gets 750MB/sec (faster than SATA3) and LTO-8 looks to improve on that.

Tapes are more expensive and have slower access time. Good for cold storage, not good as HDD replacement.