There's much to like about the new WD My Book Duo desktop external storage device.
For one, it's the first desktop external drive I've seen that comes with a built-in USB hub with two USB 3.0 ports. It also has hardware RAID, you can replace its internal hard drives easily, and it has a lot of storage. Finally, it delivers fast performance, especially when working in RAID 0, and it all comes at the affordable street price of just $280 (£250 in the UK), $350 (£315), $450 (£420), and $700 for 4TB, 6TB, 8TB and 12TB, respectively. (Australian pricing was not available at time of writing.)
If you can live with the short two-year warranty, the WD My Book Duo is an excellent USB 3.0 external storage device for your desktop computer, be it a Windows or a Mac. For other options, check out this list of top desktop external hard drives on the market.
Smart design with built-in USB hub
Taking the shape of a a closed book that's standing up, the WD My Book Duo is similar to the WD Thunderbolt Duo though with a few major differences. On the outside it uses USB 3.0 instead of Thunderbolt. And on the inside, it houses two WD Red internal hard drives instead of WD Green hard drives.
(The WD Red drive is made mainly for NAS servers, and has been one of the most reliable internal hard drives on the market. I personally use a lot of them and haven't had any failure to date.)
You can replace the two hard drives easily thanks to the lid on top that pops up with just a push -- no tool is required. WD recommends that you use the WD Red, but the My Book Duo supports any standard SATA hard drives.
Desktop external USB RAID storage system
USB 3.0, USB 2.0
4TB, 6TB, 8TB, 12TB
Capacity of test unit
6.2 x 6.5 x 3.9 - inches (9.9 x 9.9 x 16.5 cm)
5.1 lbs (2.2kg)
Windows XP or later, Mac OS 10.4 or later
WD SmartWare Pro (Windows), Acronis True Image (Windows), WD Drive Utilities (Windows / Mac), WD Security (Windows / Mac)
On its back, the My Book Duo has one micro-USB 3.0 B-female port for connecting host computer via the included foot-long USB cable. In addition, it also has two USB 3.0 A-female ports, which you can use to connect an additional two USB devices to the host computer. That's a great design feature since the My Book Duo actually adds two more USB ports instead of taking one away. I tried the two extra ports with a few portable drives and they provided enough juice to power all of them.
The My Book Duo shares the power status with the host computer. That means that it automatically puts itself in the same state as the computer, be it shutdown, sleep, or on. Most Thunderbolt devices have that feature, which is much better than the drive going to sleep on its own. Also, with this smart design, the My Book Duo is always available to the host and saves energy based on how you customize the energy-saving feature on your computer.
Versatile RAID, helpful software
Out of the box, the two internal hard drives of the My Book Duo are configured in RAID 0 for maximum performance and storage space. RAID 0 has its own weakness; if one of the drives fails, you lose data on both. For important data, you should switch to RAID 1, which protects data against a single drive failure. You can change the RAID configuration by using the included WD Drive Utilities software, which also allows for drive diagnostics, erasing, and formatting. Note that switching the RAID configuration means that all existing data on the device will be erased.