Stress testing a Pi...

If you want a Pi5 NAS, this looks like a good option:

Theo

That may be an option all right - it takes external 12V which I can probably supply. And there is one for a Pi 4...

I think the Radxa Pi4 one was released just before all the supply chain mayhem when nobody could buy Pi 4s - I think they discontinued it so I'm not sure it's actually available right now. On the Pi 4 you have to use USB rather than PCIe, unless using a Compute Module (when you lose USB3).

I'd expect PCIe to be more stable under load than USB. They use a JMB585 PCIe to SATA chip which isn't enterprise grade but seems to work well enough. Since Pi5 doesn't lose USB3, you can get 2.5G networking via a $10 USB adapter, rather than Jeff's odd PCIe switch.

The Pi4 was just a bit compromised for this use case IMO, but it looks like the Pi5 plus this HAT gets most things right.

Theo

So If I were you, I would want to understand the drives you have, know their power consumption, before making a decision.

FWIW, I only have one USB SSD running off an unpowered cable. The additional drives use a secondary power supply, but I use spinning HDDs as well as SSDs, so I needed to.

Also, the Pi 5 is a great computer, so worth buying just for fun. You'll find something to use it for.

I don't see a Pi as the ideal NAS. Yes, it can make one but there are better solutions. A Pi has other, better, uses.

My NAS solution is something like a Fujitsu Esprimo Q556 or Q957, power consumption is similar to a Pi 4 or Pi 5 and it comes in a case that can accomodate an M2 drive and two 2.5" drives. The power supply is in the case with it. ...and it's still pretty compact.

I did quite a lot of research before picking the drives that I did

Indeed. That was my thought. I could use it as another media driver for the now redundant TVs (redundant because I have watched and/or recorded all the repeats of all the shows I missed when working for a living, and wall to wall propaganda and adverts is all that is left ...) and stick high definition audio on it to play my music

Nice idea, but the plan is to reduce box count by integrating everything into one case, and so I need a small footprint board level device like a Pi.

-- “Those who can make you believe absurdities, can make you commit atrocities.”

― Voltaire, Questions sur les Miracles à M. Claparede, Professeur de Théologie à Genève, par un Proposant: Ou Extrait de Diverses Lettres de M. de Voltaire

But that's what is so good about the Fujitsu Esprimo Q556, it does get everything in one case. You need no external power supply and you need no external disk drives. You can even get a CD/DVD reader in there if you want. It's all in a box 18cm x 18cm x 6cm (approx).