In my experience, all that truly matters is that the drive is on the right recording technology (CMR, SMR, and maybe someday HAMR will be in the hands of us consumer plebs).

There are two reasons to care:

1. SMR has horrible write speeds. Data can read off the drive at the same speed as a CMR drive, but writes will be unbelievably slow.
2. More importantly, for some reason or another (I assume the write speed), SMR drives might get rejected by ZFS. There was some pretty loud talk about it several years ago, but I haven’t heard much since and do not know if this is still true (I assume it is).

If your use case involves only ever writing a small amount of data, point 1 doesn’t matter very much. If you’re using software which doesn’t care about CMR/SMR, point 2 doesn’t matter very much.

If either point 1 or 2 matter to you, then you should go with CMR drives. If neither matter, you may go with SMR drives if you so chose.

PS: Both WD Blues and Seagate Barracudas are (often) CMR. Seagate consult this page: https://www.seagate.com/products/cmr-smr-list/. WD lists SMR/CMR on their website when you look up the part number.

In my home NAS, I use ZFS and have ran all sorts of drives through it. It’s ran old consumer drives I’ve pulled out of scrap hardware, it’s ran NAS-grade drives, and it’s ran enterprise-grade drives… And since they’re all CMR, I can’t say there was much if any difference at all.

The only difference between the tiers that I find interesting/useful is the number of metrics you can pull off the drive. The fancier ones spit more metrics which could help you detect signs of failure earlier, but that requires knowing what to look for.

So at the end of the day, as long as the drive’s recording technology works with your software, you’re fine.

RE: External drives (seen in a comment)

External drives can be a great way to get disks for cheap, however they are loot boxes. What drive you get inside of them depends on the capacity, the manufacturer, and pure luck. You can generally look up the model number and see what people have said is inside, then hope you get whatever they got. (Generally, manufacturers don’t often change what they put in there, but they do change over time.)

You’re good in that there are no immediate problems with that setup. I run a largely similar setup, have run it for years, and have never had issues.

You can always add more security layers if desired, but from my personal experience and with my risk tolerance, I haven’t personally found it necessary.