[sn]

What I have done, and will continue to recommend, is to not have all identical SSDs in a RAID - they should be a mix of part number or age.

[csdvrx]

This, so much. At a previous company, mixing manufacturers (not brands) was a policy: WD or Sandisk -> Hynix or Toshiba, etc.

Funny enough, this plays very well with RAID10: with each leg made of 2 different brands, a firmware failure will not affect you.

[UI_at_80x24]

Which is the same advice given for disk-based RAID arrays. It is good advice and should be followed.

Just back sure they all use the same block size.

[etbe]

Sometimes that's a good idea, sometimes it might make things worse. A previous server that had a RAID-1 of SSDs was limited by SSD write speed. As the SSDs got old the write speed dropped significantly. If I had 2 servers that each had the same brand of SSDs then one server would need both SSDs replaced while if I had 2 servers with different brands then each server would need a single SSD replaced which would have been more hassle.

[sennight]

This is what lot numbers are for, the tracking (and in this case: leveraging) of variability between production runs. Spread multiple lots over more than one storage array and you're good to go.

[wtallis]

Multiple lot numbers won't save you from firmware bugs.

[vernie]

Isn't this the same advice with HDDs?