[jackalope]

I'd like to see the same kind of test with identical drives mirrored (RAID 1 or another suitable way to precisely duplicate disk I/O). One of the things I've always wondered is if two SSDs from the same lot are more likely to fail at the same time. It's not unusual to have such an arrangement in a newly deployed server. Longevity is (more than) nice, but simultaneous failure is still a disaster, whenever it happens. Does it make sense to provision drives that don't match exactly (in age, manufacturer, etc.) in order to avoid potential issues?

[Filligree]

Yes, it does; this is common knowledge. Using drives with similar serial numbers will seriously degrade the expected benefit of RAID mirroring.

[mikevm]

You might have this paper interesting: http://pages.cs.wisc.edu/~kadav/app/pdfs/diffraid-hs09.pdf RAID-5, for example, is a disaster for SSDs.