Currently an Apple Store exclusive, this portable USB drive is based on Hitachi’s Travelstar Z5K320 HDD. At only 7mm deep, it’s around 36% more space efficient than standard 2.5-inch drives, allowing for a casing that’s less than a centimetre thick.

The G-Drive Slim 320GB boasts a robust, stylish build, with a solid aluminium enclosure bound by a black rubberised border. In common with other G-Drives, it also has an attractive desktop icon.

It comes preformatted for Macs, and the casing does a great job of keeping the drive cool, which was backed up in tests.

In our QuickBench tests, the G-Drive Slim 320GB achieved random read speeds of 11.747 MB/s, which is pretty fast, compared to similar portable USB drives. Its random write speed of 11.414 MB/s is a little slower than we’re used to, but marginally so.

A competent but unremarkable performance is exactly what you’d expect from a drive operating using a USB connection, and that’s exactly what we got. It worked well under sub-optimal power conditions, mounting via an unpowered USB hub, and even when plugged into a fullsized aluminium keyboard.

The G-Drive Slim 320GB lacks bundled extras. There are no accessories beyond a USB cable, no FireWire connectivity and no software. But if you’re looking for a solid, reliable and very portable 2.5-inch-format drive, the slim is ideal.

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