Less power usage, less heat and less points of failureSo how does having multi smaller units make it better?
Without a model number it will be hard to pin down, but assuming something like an older ST4000NM0125 that's 6.52W Idle / 7.74W average10x4gb sas drives which are not high end ones they pull 5w each (so around 50w)
Add in the Power requirements for the LSI SAS 9207-8i and that's another 9.8W (Worst case 16.0W according to spec sheet)
So that's ~87 Watts when in operation ( ~75 Watts idle)
A Modern WD Red Pro SATA (e.g. WD141KFGX 14TB) is 3.0W Idle / 6.2W Average.
4 of those = 24.8W Average and no separate HBA needed.
The energy saving from switching from 10 drives+HBA to 4 higher capacity SATA drives is £150/year
There isn't much of an alternative - if you need the storage space you need the storage space.I need this much space so what alternative is there apart from paying more money for fewer drives that are larger capacity.
Switching to Unraid rather than ZFS and actually spinning the drives you have down would save more money (but again also has a purchase cost - of an Unraid license as well)

