Seagate Backup Plus Fast --> 2x 2TB drives inside, USB 3.0, and faster than this Thunderbolt drive; $269.99
http://www.amazon.com/Seagate-Backup-Portable-External-STDA4000100/dp/B00HXAV0X6
Also bus powered.
I don't see any evidence that it's faster than this WD version. Seagate's own page states 220 MB/s. Less than the theoretical limit of the WD drive in the article.
Not a great difference, I'll grant, but you really need either SSDs or more than a 2-drive array to saturate the Thunderbolt port.
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