At Macworld 2012, we highlighted the newly announced My Book Thunderbolt Duo drive from WDC. Each drive enclosure held two hard drives in a RAID configuration and offered two Thunderbolt ports. The units could then be daisy chained together over Thunderbolt to create a single high performance logical drive.
WDC has since announced shipping and availability of the new drive systems.
Pricing for the new enclosures has been set at $599.99 USD MSRP (4 TB) and $699.99 (6 TB) and are available online.The new My Book Thunderbolt Duo provides professionals and Mac® enthusiasts with five primary areas of performance, double-safe data protection and flexibility; ultra-fast data transfer rates for greater work efficiency; a 4 TB/6 TB large-capacity; customized dual-drive storage system with RAID 0, 1 and JBOD options; customer serviceable drives; and dual Thunderbolt ports for daisy-chaining multiple My Book Thunderbolt Duo devices or other peripherals.
To compare, the Thunderbolt version seems to carry a $200 premium over their My Book Studio Edition II drive system which provides a similar setup (4TB/$399, 6TB/$499), though without Thunderbolt performance and connectivity.
Article Link: WDC My Book Thunderbolt Duo Drive Pricing and Shipping Announced