These look compelling, but unfortunately, we know that SSDs are not nearly as reliable as spinning rust hard drives when it comes to data retention: https://www.tomshardware.com/pc-components/storage/unpowered...

(I assume M.2 cards are the same, but have not confirmed.)

If this isn’t running 24/7, I’m not sure I would trust it with my most precious data.

Also, these things are just begging for a 10Gbps Ethernet port, since you're going to lose out on a ton of bandwidth over 2.5Gbps... though I suppose you could probably use the USB-C port for that.