'Pro your decision:
https://www.youtube.com/watch?v=A2OxG2UjiV4Raid 5 would be more cost effective.
It is a good current level of protection except for offsite backups.
But will cost more due to more drive bays required for raid 6 versus raid 5.
Raid 0 has no redundancy.
Every drive adds to the storage space
Raid 5 uses the space of 1 drive for redundancy
So the capacity of 1 drive is used for redundancy
Meaning the sum capacity of all the disks minus one disk.
Raid 6 uses the capacity of two of the drives for redundancy
So the capacity of 2 drives is used for redundancy
Meaning the sum capacity of all the disks minus two disk.
My 2 cents.