WD My could mirror HDD failure - fix by reset?

Hi,
I have a WD my cloud mirror with 2x4GB (Raid1) that has been running for about 3 years now, mostly used for Apple Time Machine automatic backup via Wi-Fi. A few weeks ago drive one failed (red light), so I got a new usb drive to save the data from the working drive and was contemplating whether to replace just the failed drive or both or get a new WD my cloud (not so much difference from buying 2 new drives). However, when I tried to do the USB backup it wouldn’t work until I did the short reset procedure. After this, the failed hard drive magically appears to work again und the mycloud is busy restoring it from the other drive.
My question is - can I trust that the reset seems to have fixed the problem or is the drive likely broken anyway? How long do these drives usually last?
Related question - I guess the WD red drives are the standard choice for replacement. Where I live the Seagate Iron Wolf drives are a bit cheaper and also recommended for NAS use. Is there any reason to not use these in a MyCloud Mirror (not sure if I have V1 or V2)?

I’m sorry if this has already been asked elsewhere, couldn’t find the information I was looking for.
Best regards,
Thomas

Hi,

You could refer to the following link: https://support-en.wd.com/app/answers/detail/a_id/14277