storage - 3-way RAID 1 vs. 2-way RAID 1 + hot spare

Assuming the following parameters for a new server storage configuration:

• All drives are SSD


• Few large drives are preferred over many small drives


• RAID 1/mirroring is preferred over RAID 5/6/parity


• A dedicated hardware RAID adapter is preferred over software RAID or storage spaces


• Edit: Only one single RAID array is required

So to me it all boils down to a three drive setup with either

• 2-way RAID 1, with hot spare


• 3-way RAID 1, no hot spare

While the obvious advantages of the 3-way setup are

• Potential read performance bonus


• Concurrent loss of two drives supported

Are there any points to make in favor of the 2-way hot spare setup except maybe these?

• All data is also written to the third drive, wearing it out like just like the other two, while a hot spare won't be written to before a potential array rebuild.



• Potential write performance penalty due to all data needing to be written three times opposed to twice (which could be negated by the hardware RAID controller)

Edit: Added parameter to clarify that only one single RAID array is desired