Yas is correct on the pricing, they have the by amount of storage option and I forget the how the tiers are setup but with that you have no limit on the number of drives. What I have seen so far and this is fairly newly put in. Backups run a little bit faster, restores are much quicker, downfalls: does not allow for use of powerpath and multiple hba's which would definitely increase things, also you have to be careful about how many/little drives you add and use to get a happy medium for your environment.