@flatline That's a vague question with lots of answers depending on a lot of factors. I use ZFS on Ubuntu Server 20.04.
@flatline I have about 35 12-bay rack mount Qnaps in use at work with up to 4 years on them so far. They aren't bad but somewhat expensive. The OS is a somewhat quirky Linux and as long as you stay up to date on their software releases you should be good. The hardware is quite good.
For personal use I am looking at a Terramaster with Truenas Scale as soon as that's released. Something along these lines: https://joelduncan.io/freenas-on-terramaster-f2-221/
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