XRAID-2 Hot Spare or Expansion with FlexRaid

Yes, I have been thinking about the Pro, but it has quite a hefty price tag! I guess my question to Netgear is why not provide 4-disk RAID 6 on the NVX; even if not that many folks used it, it would seem a logical option to include (if nothing else, just to make the sales documentation look better). Looking at the competition makes me think that Netgear maybe should have considered a 5 bay RAID 6 device as the logical upgrade from the NV+ (i.e. they ought to have brought out something to compete with the Qnap 509). I don't intend migrating from my ReadyNAS's, but the 509's price makes it difficult to ignore as an alternative strategy.

Bri