If you need the speed of eSATA or FireWire on your PC or Mac, then go with the Studio Edition II.

Though its write performance is less than stellar, the My Book Studio Edition II provides copious amounts of storage space, a sleek look, and plenty of connection options... If you need to store 722 hours of HD video or 1.5 million MP3s, this is a good storage device for your needs.

The My Book Studio Edition II makes a decent direct-attached storage solution for those who need to extend a computer's storage space or want a large backup drive. The drive's rather buggy firmware might turn many users away, however.

If you're a non-Thunderbolt Mac owner that needs a good amount of external storage, Western Digital's My Book Studio Edition II works well... down the road if you need to replace the drives inside the Studio II you'll have to be sure to source Caviar Green drives from Western Digital.

The WD My Book Studio II benefits from this upgrade to the largest commercially available hard disks, offering around 6TB when the internal drives are striped together. If you value data integrity over capacity and slightly faster write speeds, you’d be advised to mirror the drives.