This seems a little over the top to me.

Just use a magnetic hard disk and your data will be fine for many decades if not centuries. You don't need M-Blu Rays (which have very limited capacity anyway). A hard disk is cheap and stores several Terabytes.

You obviously need to store the data in a physically remote place like your shed, car or safe deposit box in case your house burns down.

Never, ever use a SSD if you want your data to be safe for any amount of time. What's worse, SSDs can fail unexpectedly with almost zero chance of data recovery.

> Just use a magnetic hard disk and your data will be fine for many decades if not centuries.

A few months ago I needed to pull from an offline backup. The disk, which used CMR and was purchased new from an actual computer supply company (i.e. not Amazon), was burnt in for about 72 hours before it was loaded up with data and shoved in a padded box. Ten years later, the drive was pulled, and there were so many media surface errors that most of the data was unrecoverable. (I haven’t bothered opening the drive to see if there is some obvious sign of what exactly failed.)

In my case the backups were created in multiples using two different brands for exactly this reason, and the second copy was fine. But I wouldn’t say it’s the case a single magnetic disk can take the place of BD.

Mechanical disks are also getting expensive. The disk purchased to replace the failed backup was being sold at three times its original release MSRP. Some of this is due to the AI hysteria but some of it is also that the market is shrinking and becoming K-shaped.

Tell that to my circa-2000s WD MyBook that clicks and fails to initialize after ~17 years in climate-controlled storage in its original packaging. I'm about to attempt surgery on the heads to see if I can get it going again.

I also have a binder full of DVD-Rs, of about the same age and containing mostly the same data, that all read perfectly with no issues.

You're asking for trouble if you count on just one backup solution to keep your data safe.

Even if perfectly held still in a sealed box with perfect conditions, hard disk drives need controllers; they need the chipset to drive them, which has ROM and other stored microcode that is susceptible to bit flips due to cosmic ray impingement. I've traced faults in a few 20+ year old HDD's due to failed controllers likely due to such loss (either in the main controller fail, a ROM/BIOS chip fail, or less likely but still possible the cache IC, or motor controller). The data is there on the spinning rust, you just won't have a way to access it.

The failure of SSD's you warn of and the way the HDD's fail due to a dead controller aren't that different.

This won't happen with a physically written media like a CD, DVD, or Blu Ray disc. With physical media, you're separating out the media from the reader (the drive). If your disc reader dies or you cant find it, etc, you can go find any another one on ebay even decades from now, very likely.

Doing surgery on an HDD controller PCB to replace a dead controller, while possible, sucks, and may be incredibly difficult if not impossible to source parts for in the future.

> Just use a magnetic hard disk and your data will be fine for many decades if not centuries

It is absolutely not safe for many decades. If you haven't encountered any drive failures yet — you're lucky.

> A hard disk is cheap and stores several Terabytes

You should check prices again, I wouldn't say cheap considering price bump during the last year (or around so). M-Disks are way less convenient, but pretty reasonable for their cost.

Just use a magnetic hard disk and your data will be fine for many decades if not centuries.

Comically untrue, and trivial to verify that it is.

You obviously need to store the data in a physically remote place like your shed, car

Let's make it worse by keeping them someplace with terrible environmentals.

If you're gonna be wrong, don't be just a little wrong...

Offline HDDs are not a reliable long term data storage. Not even for a few years.

Hard drives are a safe option if you keep them redundant, online, and scrub them regularly. They are not a good long-term offline archive format.

Hard disks aren't even rated for one decade.

Hard drives are way bigger, but M-Disk is more reliable for very long term storage.

With the decline in quality I am no longer confident my HDDs are actually a save backup strategy.

I have so many photos of vacations and people who I've buried over the years, that I don't want to lose.

So I was thinking about using Blu-ray M-Disks as well, these last couple of months.