Storage is always a problem. 4K movies, high-res photos, and new games all take up a lot of hard drive space. Almost any new laptop or desktop computer you buy will have a USB 3.0 port, giving you super-fast data transfers from external storage to your PC. All new MacBooks, iMacs and the Mac Pro have a Thunderbolt port, with even faster data transfer speeds. While you can easily buy a portable drive with a Thunderbolt port or a USB 3.0 port, what if you want both? HGST's new G-Drive Mobile Thunderbolt is just the ticket.
What Is It?
The G-Drive Mobile Thunderbolt is just one member of the larger G-Technology family; HGST has a line-up ranging from simple and cheap portable hard drives to multi-drive, multi-thousand-dollar disk enclosures. If you're not familiar with the name, it's because HGST used to be Hitachi; the name change came when the storage component of that business was sold to Western Digital.
Hitachi has had and continues to have a good reputation when it comes to the reliability of its storage devices, and the G-Drive Mobile Thunderbolt should be no different.
Inside the Mobile Thunderbolt is a 1TB, 7200RPM spinning-disk hard drive; it's the only option for this particular enclosure, and if you want a faster SSD-based solution you'll need to shell out for the G-Drive ev SSD or another Thunderbolt SSD like the 240GB LaCie Rugged ($469.95). HGST claims read speeds of up to 136MB/sec — nowhere near the practical limit of either USB 3.0 or Thunderbolt, but making the absolute best of its traditional hard drive.
The convenience of having both Thunderbolt and USB 3.0 in a single portable enclosure means that this drive is not particularly cheap. At $299.95 through the Apple Store, it's almost three times as expensive as a USB 3.0-only drive like the WD My Passport. Look at another dual Thunderbolt-USB 3.0 drive like LaCie's 1TB Rugged ($249.95) or the Buffalo 1TB MiniStation ($279.95) and the price gap closes considerably.
What Is It Good At?
HGST's entire G-Drive family is tougher than your garden-variety, corner-store portable hard drive enclosure, and the G-Drive Mobile Thunderbolt follows the same trend. Despite containing a relatively slim and small 2.5-inch SATA hard drive, there's a good deal of aluminium bulk to this case — it measures 127 x 83 x 18 mm and weighs 295g, reminding us somewhat of the visually similar ioSafe Rugged Portable (although that's much heavier, by virtue of its disaster-proof design).
The sturdy metal build means the HGST Mobile Thunderbolt will be perfectly able to work through the odd bump, accidental drop onto carpet, or daily commute in a backpack or purse. It's not waterproof, or crushproof, or drop-proof, but we have faith in the quality of its construction. There's no undue flex or wobble in the drive's connectors, which is an achievement given the wide and slim aspect of USB 3.0.
The opposite end to the connectors is where the G-Drive Mobile Thunderbolt's single status light lives; it turns on when the drive is connected to a computer and powered up, and flashes whenever there is disk activity.
Since the Mobile Thunderbolt's drive is a 7200RPM unit, it has a significant performance advantage over a 5400RPM disk; it's not going to be able to perform at SSD speed levels, but in our testing with a 256GB SSD-equipped PC test-bench on USB 3.0, we easily and consistently achieved 129MBps write speeds and 131MBps read speeds in transferring a 25GB video file (of TimeScapes in 4K). With the same 25GB file being transferred from a similarly fast 512GB PCI-e SSD inside a Mac Pro over Thunderbolt, we actually hit the drive's rated 136MBps speed in reading and found 134MBps in writing the initial file.
These performance figures mean that the HGST G-Drive Thunderbolt is perfectly capable when it comes to medium-duty file transfer tasks; with it connected over USB 3.0 or Thunderbolt, it's more than fast enough to store an Adobe Lightroom or Apple Aperture library of high-resolution photos from your camera, keeping them stored externally and accessing them whenever you want to view or edit.
If you tried to transfer 4K or multi-stream video back and forth for a bit of Premiere Pro or Final Cut Pro work, though, the upper 136MBps transfer limit would start to be a limitation; this is where you'd definitely need to shell out for an external SSD.
What Is It Not Good At?
There's no question that the Mobile Thunderbolt can't compare to an external Thunderbolt or USB 3.0 solid state drive in terms of outright speed. Newer SSDs are able to reach speeds nearing 400MBps over either interface, nearly three times as fast as even the G-Drive's speedy spinning disk. You obviously pay a premium for an SSD and take a significant hit on available storage space — so buying one is exponentially more expensive — but when you're working with huge video files, it's almost mandatory.
We did also find that the G-Drive Mobile Thunderbolt's sharp front bezel did get scratched quite easily. It doesn't affect the performance of the drive itself in the slightest, of course, but as with other anodised aluminium devices in that oft-imitated MacBook finish, it's relatively easy to scuff or mark the G-Drive if you're not careful. The worst that can happen is that it starts to not look so shiny and new, of course, especially around the slightly embossed G-Technology logo on the centre front of the disk.
Being a dual-Thunderbolt-and-USB 3.0 drive, the Mobile Thunderbolt is suitable for use on both Windows and Mac OS X. We did most of our testing on Windows 8.1, but found that the disk was initially formatted for Mac — it's not surprising, and not even necessarily an impediment, since reformatting is a two-minute job, but it's worth considering if you buy it for your Windows PC and can't find it in My Computer.
Should You Buy It?
It's relatively expensive for a spinning disk drive, but that is almost entirely justified by the HGST G-Drive Mobile Thunderbolt's combination of sturdy and attractive design, versatile USB and Thunderbolt I/O mix, and adequate medium-duty mid-130MBps read and write performance. If you're moving data between Mac and Windows machines regularly, or if you need an external media drive with acceptable performance for photo editing and storage or basic video editing, the Mobile Thunderbolt does a good job.