Bill, you seem to be missing a key point of ZFS - the 'I' in RAID. ZFS is inexpensive. All the systems you mention, sure they've done it before and often better, but they cost $$$. ZFS comes with the OS at no additional charge. It offers some of the benefits of technology that belonged in the high end and enterprise markets to low and mid range users. Sure, some of the technologies are available in other file systems for the lower end market but ZFS brings them together and gives a pretty clean interface for managing what is underneath a relatively complex system. It's ideal where money is tight, knowledge is limited and performance isn't a driving force. »