QTier or SSD Cache or Nothing?

[Enquiries]

I'm considering putting m2 modules in my 453E and using Qtier.

I have 4 HD Red Plus drives (4tb each) in a raid 10 and my network is all 2.5gbe.

The NAS itself is used for a variety of uses:
Small documents read occasionally.
Some database access.
Occasional libre office container
Media from small photos to 4k movies.

I was hoping Qtier would give me some more space and speed. The more I read the more I'm confused .

Does Qtier make sense?
Is Caching better?
Should I just pass on it all?
What is the best M2.nvme's to pick up for this NAS?

[ed]

Yes, this NAS is all-in-one solution. And it is great for multimedia.
Qtier is a combination of HDD and SSD volumes. But it is more useful in business environment. Based on your schedule Qnap will move data to SSD volume. So you will only see speed improvement after qtiering daily rutine runs.
NVMe cache will give you instant benefit simply because all data first land on SSD. Read cache use a copy of data to speed things up.
If you want to maximise the space and keep your performance always fast, I would set up a NAS to run its OS on NVMe pool. This way all data is first placed on fast SSD volume. And it doesn't duplicate data as NVMe cache would.
You can then enable Qtier which will move less often accessed data to HDD volume.

I hope these links help
https://www.qnap.com/hu-hu/how-to/tutori...erformance
https://www.qnap.com/en/how-to/faq/artic...-ssd-cache

When choosing NVMe for caching you need to look at reliability ratings such as DWPD/MTBF. Here are a few on the list
https://nascompares.com/answer/nvme-m-2-...dwpd-mtbf/
Caching means a lot of read and write operations, unlike regular storage situation.
You would need to look at models with 0.5DWPD and above

970 pro – 0.66DWPD

Synology SNV3400 – 0.68DWPD

Seagate FireCuda 510 – 0.7 DWPD
Seagate IronWolf 525 – 0.7 DWPD
Seagate Firecuda 530 – 0.7 DWPD
Seagate PS5 Game drive – 0.7 DWPD

Seagate FireCuda 520 -0.9 DWPD
WD Red SN700 – 1.0DWPD

I hope this helps.