Adding second SSD to mirror datastore...same exact drive?

[jimphreak]

I've got a Samsung 840 EVO 500GB SSD in my home VM server that I use as a datastore for my VMs. I'd like to add a second and mirror it in a RAID1 array for redundancy. Should I be adding the exact same drive or would the 850 EVO work as well?

 

[KapsZ28]

It won't be an issue just so long as they are the same size. In a work environment, I would say to keep them identical.