Capacity is only effective if you can buy it
Disclaimer - NetApp marketing guy
I have to admit - maximum capacity isn't the all-flash attribute I normally spend my day on. But here are the numbers for the NetApp AFF product which are not easily ignored (well they shouldn't be):
22PB Raw Capacity = 480 drives * 3.8TB = 1.8PB / Array * 12 Arrays / Cluster = 21.9PB / Cluster
18PB Usable Capacity = 82% or 1.5PB / Array or 17.9PB / Cluster
80PB Effective Capacity @ 4:1 ~ 80PB / Cluster
Most flash experts are turning their attention to scale-out. It's one of the reasons we are so bullish on SolidFire which adds a new storage controller for every 10 SSDs.
And finally, at the risk of stating the obvious, the capacity of FlashArray is effectively zero since it's not shipping ;-)