Welcome to the Lounge

Ron Anders wrote:

Including hosing a Home Automation stack that bridges...

1. Aye!
2. For me, most definitely. Your mileage may vary. It all depends on what you need to do with your files, and what you expect from a NAS (compared to other alternatives).

• NAS disks are meant to be constantly spinning, 24 hours a day; unlike desktop disks, which may get stopped now and then and be gently spun up again (mostly to conserve battery power on laptops).
• Even so-called 'server-class disks' might not be appropriate for a NAS: even servers will not be constantly accessing their disks (at least in theory), and the way they do it is optimised anyway. Sure, they will be 'constantly on' all the time, and thus place heavier demands on the disk, but a well-tuned server will have plenty of memory to cache whatever the kernel needs, and limit disk reads (and especially writes) to the bare minimum. It's just when an underpowered server relies on disk swap as opposed to memory that the disk gets stress-tested to its utter limits (and that's why 'server disks', unlike 'desktop disks', are manufactured differently).
• By contrast, NAS disks are working all the time. They will be fetching tiny files (measured in bytes) as well as huge ones (measured in GBytes), and the combination with which these will be fetched/written to is unpredictable. They will serve files for several different operating systems — thus, they will not have beforehand knowledge of which files to save in memory, or how to organise the filesystem so that it prioritises some files over others. That's the kind of data that, say, Windows, Linux, or macOS know beforehand — and organise disk space to make it more efficient (and that's why hard-core Linux sysadmins will also fine-tune things like partition tables, because they know that some things have to be served faster or more often than others). But a NAS will be dealing with files coming from all sorts of systems and cannot 'predict' what is the 'best' layout it needs. Consequently, the disks have no choice but to be always spinning.
• On a NAS, you expect 'network speed' to equate to 'disk speed'; in other words, if you have a Gigabit Ethernet LAN at home, you expect files to be transferred to and from the NAS at, well, Gigabit speeds (or what would be the point of having a Gigabit LAN in the first place?). To make matters a bit more complicated, if you have a small office (or all your family members have multiple computing devices), you expect that everybody is able to transfer files at Gigabit speeds — and that the NAS can handle them. Ideally, inside your LAN, you wish the LAN to be the bottleneck, not the NAS. But, on the other hand, it's also pointless to pay more for a faster system that is adequate for a 10Gbps Ethernet LAN if all you have is four computers with 1Gbps Ethernet cards. NAS disks, therefore, have to be able to handle 'wire speed' for your environment — and not all disks can handle that, or, if they can do it at 'peak performance', they might not be able to do it all the time.
• Finally — and against my own expectations! — SDD is not always better than HDD (in the sense of being faster, consuming less energy, and lasting longer). It's actually much more complex than that. Contemporary OSes have filesystems that have been redesigned to take into account the very different approach taken by SDDs compared to HDDs, and, under most scenarios — meaning: your desktop computer or your laptop — SDDs will almost always be better, faster, more energy-efficient, etc. They will also degrade differently over time, as bits of solid-state memory get 'burned' out and reassigned (this is not very different to what happens with the magnetic properties of a disk surface — everything degrades due to entropy, it's just a matter of how each material degrades, and what solution is adequate to deal with that degradation over time). The advantage of 'no moving parts' (which, mind you, is a huge advantage!) may be offset by the effects caused by heat dissipation — especially when talking about 'always on' systems that are under constant stress. The list goes on, and at the very least, I understood that there are still very good reasons why disk manufacturers haven't dumped all their HDD production lines and replaced them all with solid-state devices.