On the surface, Freecom's Thunderbolt and USB 3.0-equipped Mobile Drive Mg seems to provide the perfect blend of portability, performance and versatility. There are no design surprises sprung, the drive is essentially an update of a previous dual-port model (Firewire 800 and USB 2.0), and sports the same slim magnesium case and lightweight pocket-friendly chassis. To be fair, there's no real need to update this basic design as it still complements the Mac perfectly, and won't look out of place next to PCs either.
Freecom claims the magnesium design ensures the drive stays cool, and judging by the heat emanating from it after even a relatively short period, it appears it's doing its job as a glorified heatsink.
As the drive is self-powered, you'll only find the two connectors – one USB 3.0, the other Thunderbolt – on the back of the drive. Surprisingly, though, the drive indicator light is also housed here, which is a strange choice. Thankfully, cables for both ports are provided.
The drive is pre-formatted ready for use on the Mac, which means it'll work out of the box with Time Machine, but there is a hidden partition containing the necessary software to reformat the drive for PC use too. Other included software includes an energy saving tool called Green Button that puts the drive to sleep after a specified period.
The key issue with the Mobile Drive Mg, as it would be with any Thunderbolt-equipped drive that works with the smaller 2.5-inch hard drive, is that you'll never get to utilise the full bandwidth of the Thunderbolt interface. That's most evident when benchmarking the drive in QuickBench, its peak read/write figures of 106/102MB/s in Thunderbolt mode similar to its USB 3.0 figures.
You'll be similarly disappointed if you plan to copy large files to the drive, as speeds max out well below their potential. However, we were pleased to see the drive perform much quicker in our small-file test, copying a 36.5GB folder containing over 60,000 files in just 11 minutes and 30 seconds, which is half the time it took to copy the same folder to similar portable drives sporting the USB 3.0 interface.
The drive is undoubtedly well designed and sits neatly alongside modern Macs. It's slim, light and pocket-friendly too, something not usually associated with Thunderbolt drives. Performance – particularly with smaller files – was impressive as well. If you're running an older Mac with Thunderbolt, but not USB 3.0, then this drive will make a big difference.
We didn't like
The relatively slow transfer speeds using Thunderbolt make us question the point of paying a hefty premium for that interface when you can get broadly similar performance for much less from a USB 3.0-only portable drive. We were also unimpressed with the drive's USB 3.0 performance when connected to a PC.
If you're happy to pay a large premium for a tiny performance gain over USB 3.0, then the Freecom Mobile Drive Mg will appeal, but we'd suggest looking at the USB 3.0-only model, which is much cheaper.