It'll just flag/correct if possible whatever inconsistencies you have in the filesystem, with its native tool.

Nothing wrong I guess, as long as you don't care about the data

Use a Windows machine and chkdsk.

NEVER do that

For good measure you can do a surface scan too

yea, sure, kill it completely

I would do a single ZFS pool with the three drives.

that would be ideal

So if you have 6 SAS drives running 24/7 the turnover point from this investement would be at roughly 5 years. IMO not worth it at all.

https://www.westerndigital.com/pl-pl/products/internal-drives/data-center-drives/ultrastar-dc-hc580-hdd?sku=0F62796

EDIT: was thinking Firecuda as they are SMR rather than the CMR barracuda, so read that SMR drivers are considered to be better.

read again

because they are different products, they have different amounts of them, there is different amount of them on the market at different prices, and the demand is different

this budget might be enough if you live in the US and buy cheapest used drives there are

Disregard the advice about SSDs. Start with 1 NVMe for boot and only add more if you have a need. Either for running VMs or if additional cache is actually needed.

I trust MB SATA more in terms of reliability. HBAs tend to overheat too.

However, if RAID topology allows, I'd try to spread the drives such that either one of MB or HBA failing completely would not bring the array down (RAID10 with 1 HBA, or RAID5/6 with 2 HBAs).

Yea, the only people who praise apple's cross-device compatibility are people who own only apple devices. Go figure.

They have no interest in any kind of cross-device compatibility beyond how it might serve you ads better/faster.

What? It's apple that's lacking compatibility. Even SMB is gimped. You got enclosed in an apple garden and you like it, ok, but your assessment is completely backwards.

they are not selling your data, that would be dumb