Raid 1, different manufacturers. Is it worth it?

Question

Hard disks

There is an Adaptec 6805e where there are two 3TB in the mirror, Seagate Constellation CS (ST3000NC002). (only read cache included) There is a need to expand the storage by purchasing two 3TB Western Digital Caviar Green (WD30EZRX). I am aware that the greens are slower, but last time the Seagates fell one after the other, showing that the same models die at the same time.
Does it make sense to make RAID 1 pairs from different vendors?
all good.
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I don't confuse a raid with a backup - critical data is copied according to a schedule to a remote NAS.
I encountered mdadm more than once, but still decided to take a hardware one because:
Raid on Windows, NTFS is therefore hardware (I don’t have faith in a Windows soft-raid - I tried it)
Why so much hate for adaptec? I myself had problems with LSI (hardware), except for a shrill squeak during degradation, there were never any complaints about adapters.

Answer 1

About different manufacturers: the topic is correct, the eggs will be in different baskets.
But. The type of hard disk must match the task. Greens from wd are not for raiding, they are for very cold data such as movie storage. For your tasks, the ability of the hard to withstand the vibrations of the entire group of hards is important, the ability to disable the hard cache so that only the controller cache works, the error probability parameter (10 to such and such a degree) and the guarantee in the end are important. Greens are guaranteed for 3 years, for black wd series, for example, 5 years. They are actually more reliable.
In general, you need a drive designed for servers and storage. Your controller, by the way, can cache using ssd. This will greatly increase productivity for typical operations.

Answer 2

It makes sense to use Glucotec only as a controller, creating an array programmatically. Otherwise, you risk catching a glucodrome, with data loss, of course.
By the way, do you have a mirror instead of a backup? I remind you that raid1 is not a backup.
A soft raid can be assembled from any junk, the main thing is that the sizes are approximately the same.