Thanks for the reply.
As a newcomer to Unraid, I wasn't aware that I could achieve redundancy with just one parity drive and two data drives without needing them to be mirrors.
So, if I understand correctly, I can keep one disk as the parity drive and the other two as regular data drives. In the event of any drive failure, I can simply replace the failed drive without the need for mirroring.
Just one more question: does it matter which drive I designate as the parity drive, or can I choose any of the three drives for this role?