I don't think anyone has long term experience with qlc storage. It isn't old enough for that.
Manufacturers have most likely simulated accelerated aging using heat, and set their warranty accordingly.
Don't expect more than what the warranty promise.
There is no consumer long term digital storage solution. Except multiple copies and continuous migration to new media.
I recently upgraded. Plenty of free disk storage now. Feels strange. Difficulties sleeping.
Sure.
It will break, just as reliably as any other HDD if you drop it high enough.
You need SATA and 12V.
If you know the play time and the size you want, you can calculate the total bitrate you need to set. Subtract the audio bitrate from the total, and you get the video bitrate to set. Make a spreadsheet and fill in the numbers.
Depending on the contents and aspect ratio, you may get bad results. Setting a lowest acceptable quality is better, but then size can vary a lot.
I think that you will get better bang for your buck with much larger drives. I think the cheapest per TB is currently somewhere between 16TB and 20TB for new drives. In addition you save power and especially drive bays compared to 6TB drives. Drive bays, ports and PSU are very expensive as well!
The most important thing you can do, to prolong the life of the HDDs, is to NOT do a full overwrite every month or so. Sync instead.
Do as little as possible to make the contents of the HDD an identical copy of the source.
There are many sync utilities and backup softwares you can use. I use a script and rsync.
Using a sync utility like rsync it is even possible to efficiently make versioned full snapshot backups. Then a new timestamped snapshot backup is created by comparing the previous snapshot with the original. Files that are in the previous snapshot are hardlinked from the previous snapshot, which save time and storage. Only new or modified files need to be copied.
This way it is very fast to create a updated snapshot and, as long as you have not made large changes to the original files, every new snapshot takes up very little storage.
I have two SSDs in my PC. The main SSD is used as normal with the OS, programs and user files. And a secondary SSD holding versioned rsync snapshots of the user files. Every boot a new updated snapshot is automatically created. Also old snapshots are automatically deleted as needed, so at most only 7 daily, 4 weekly and 4 monthly snapshots are retained.
I also have two multibay USB DAS. One primary DAS is used for media files, movies and so on. The primary DAS is also used for manually triggered snapshots of different folders on the main SSD. The secondary DAS is used for rsync snapshot backups of the main DAS. The primary DAS is usually always turned on with the PC. The secondary only now and then to backup the primary DAS.
No problem.
Most external single drive HDD enclosures run on 12 volt via a simple barrel jack. You might consider a dock that can take two drives. Then you can use the 2.5" in combination with a 3.5" drive.
To save power I think you want to avoid having the HDDs spinning all the time. Instead use a large SSD with your computer. Less power. And use the HDDs to replace and update contents on the SSD. You can pack away the dock between uses, together with the HDDs in a padded case.
Here is an example of a 2 drive dock that runs on 12 volts, can use both 2.5" and 3.5", can handle >20TB drives, use USB C and seems generally decent: (I have no personal experience with it.)
https://sabrent.com/collections/docking-station/products/ec-ch2b
When it comes to HDDs, I'd go with drives that have 5 years warranty. Exos? The biggest you can afford.
And a nice padded water proof padded box...
Yes. These hardware devices are called "computers". They run software that use the Gutmann algorithm to erase the contents of a hdd.
Today hdds are more likely to be physically shredded in order to destroy the data on them. Faster and less labor intensive and less likely to be used wrong.
Superparamagnetism is used to "flip" magnetic fields of small particles on drive platters, in order to record data.
https://en.m.wikipedia.org/wiki/Superparamagnetism
There is a slow relaxation over time because sometimes particles flip spontaneously. This means that after a very long time the magnetic patterns on the platters will become more and more random and errors will appear. Error coding, larger regions, and parity and similar tricks can minimize the problem. Higher densities can make it worse.
The rate of relaxation depends on the sizes and density of the magnetic regions, the magnetic properties of the material, external magnetic influence and temperature. If the temperature was absolute zero and no external magnetic fields were present, the magnetic properties of a hdd platter would last forever.
Modern large capacity hdds are filled with helium for cooling and to create a gas cushion between the platters and the reader heads. Since helium is a very small molecule, over time it will leak out through the case of the hdd, making the hdd performance reduced or fail. The helium will slowly leak out, even if the hdd is not being used.
Typically hdds fail early, after less than 10 years, due to vibrations, drops, head crashes, overheating, misalignments and failed electronics. Not because of magnetic relaxation or helium leakage. But eventually magnetic relaxation and helium leakage will cause problems.
No, but I asked the owners of the website and they say that you should not give up but keep trying and also reload the page and perhaps click on some of the ads.
Try to create a disk image using ddrescue. Then you can try to mount the image, repair the filesystem on the image and extract files from it.
Never work directly with a bad hdd, except to image it while mounted read-only. The hdd is likely to deteriorate as you work with it.