Large capacity NAS advice build/buy?

[antimonkat]

I currently have a 12 year old Netgear Readynas Ultra 6, I upgraded the firmware to the last version of the software which got me a lot more milage out of it, but the intel Atom cpu is too slow to run plex, and at this point it's capacity is maxed out, it takes a week to do a parity rebuild and volume expansion.

Currently it is running 4 20 tb drives and 2 22 tb drives for a total raid 5 (X:raid) volume of ~93tb once it finishes it's current re-sync and expansion.

I hesitate to even try putting 24 or 30 tb drives in it a i don't think it will like HAMR or SAS, no idea if when sata versions with CMR will be available and it's pretty dang full, only about 8TB free, so needless to say I think it's time for a new NAS.

I've never built a PC before despite being technical, I could probably manage but picking compatible parts always has me a little nervous, I like UNRAID and think I've seen enough videos I could manage that well enough, so building a NAS is possible, but I have somewhat specific requirements from the builds I've seen.

On the other hand, the main nas I am considering is the ds2422+ from synology. 

Pros: 
- 12 bays, double what I have now, plus expansion chassis
- SHR tech so I can add and replace mixed capacity drives as I go as I've been used to for the last 12 years on the netgear
- right form factor, low (relatively) power
- versatile software, more than I will ever use
- ready to go out of the gate

Cons:
- Price
- Features I don't need or are likely to use
- 108 tb single volume limit?  Unless that's been updates with later version of DSM
- not going to use their drives, EXOS is just too price compelling and higher capacity
- would want to instantly upgrade to 10gbe and nvme slots with the card

for a diy nas, I would need unraid, so I can continue my JBOD array of mixed capacity disks, even with the performance hit I take vs traditional raid

Pros:
- flexible hardware
- nearly unlimited single volume size? (28+2 drive limit not withstanding)
- Likely way cheaper to build, but how much exactly? half?

Cons:
- finding it hard to find a case in a form factor I like
- can't run multiple volumes if I wanted to, but shouldn't need to
- not experienced with pc building
- limited software ecosystem 

My requirements/wants:

- desktop form factor 
- low power ish
- low noise ish
(if not for those 3 factors I'd go 45 drives or a refurb supermicro server case) 
- at least 10+ bays, really 12 seems good
- really prefer hot swap cages
- 2.5-10gbe 2+ ports
- ability to have mixed drives used efficiently
- ideally 1 single volume (mapped network drive)

so Basically it comes down to the ds2422+ (or some future refresh that still supports SHR and maybe a larger single volume) 
or something like a fractal define 7 and give up the hot swap cages and have to source enough drive trays for it
or something else I don't know about, that's where you guys come in hopefully?

I can find 8 bay small cases for a build with hot swap, didn't find any non server, desktop ones that did more?

Oh, use case, basically I just want a large, network accessible single array for a media library that is always on and independent of my desktop pc running.

not worried about Upnp or dlna though that would be nice to have, I'd like to run plex again without the cpu getting choked out with background tasks, not even really worried about transcode.  Not that worried about other things like synced backups, and such like that.

I just want a big network available drive volume.  

Do I have my options pretty well figured out, or is there a diy solution I'm missing?

[ed]

Considering your needs and preferences, it seems like you've already narrowed down your options quite well. Both the Synology DS2422+ and a DIY NAS with Unraid have their pros and cons, and you've highlighted them effectively.

Regarding your concerns about the single-volume limit on the Synology DS2422+, it's worth mentioning that there are hacks available that can potentially bypass those limitations. However, keep in mind that such hacks may void your warranty and could potentially introduce stability or compatibility issues. Proceed with caution if you decide to explore this route.

On the other hand, building a DIY NAS with Unraid offers unparalleled flexibility, allowing you to tailor the hardware to your exact specifications. However, it does require a certain level of technical knowledge, patience, and ongoing maintenance.

If you prefer a hassle-free solution with robust performance and features, you might want to consider a QNAP system like the i5-based 74 series. These systems offer powerful performance, ample storage capacity, and a user-friendly interface, making them well-suited for your needs without the complexities of DIY setups.

Ultimately, the choice depends on your priorities and comfort level with DIY projects. Whichever option you choose, ensure it aligns with your current and future storage requirements.

[antimonkat]

Thanks for the reply, honestly I haven't really checked out or been exposed to qnap.  I suppose I should do some research on the channel about them, maybe they fill in some of the gaps of the synology.  I know at least you can easily(?) swap the os on them.   I didn't see a specific i5 75 series on amazon, but I did find this 12+4bay model and while it has n Atom processor, not an i-5, it is an 8 core? 
QNAP TS-1655-8G-US 16 Bay high Performance and high-Capacity Hybrid NAS with Intel® Atom® 8-core Processor
Also, I don't know a lot about asustore either, regarding software interface and capability, but they do have an attractively priced 10 bay...  
Asustor Lockerstor 10 AS6510T - 10 Bay NAS
A
main thing I've seen on them is their all flash nas servers, I'll check into this model too, see what I can learn.
Thanks for taking the time and validating my findings, least you've opened up a few new avenues of research for me. 
Even looking (after posting this) at all the nas case videos on amazon and ali that the channel did, more or less confirmed not a lot going on for 12+ bay desktop cases without going tower or rack.  
the qnap at least has 4 2.5 bays I can slot some drives in and comes with 2.5 gb for a little less than the synology, that might be a good fit depending on their software and any limitations I discover and that asusstore comes in at either $500 less, or $500 more depending on config, but 10gbe included either way, and 10 bay is probably enough....that still gives me another 88tb or about double my current capacity limit.  I just know nothing about their software implementation or ability, like if either asus or qnap have something similar to SHR / x-raid.  hope there are videos out there on these guys, or similar models anyway. 

Looks like there are, and I have a few queued up. Thanks. This channel is so helpful. I didn't realize that asustor was so old. probably why its such a good price.