Despite years of development, the Ultra Mobile PC (UMPC) concept is still far from perfect. Essentially, there are two problems: Windows needs extensive modification to run on a device of this size; and the current hardware required to run a full version of Windows necessitates a large battery to give adequate life. However, Sony partially overcame both of these significant hurdles with the VAIO VGN-UX17, and is back with this updated version.

The UX27 comes with Vista Business as standard, so you get the specially designed Tablet PC tools. These are capable enough to avoid needing to use the inevitably fiddly keyboard for even awkward tasks such as entering website addresses. Sony backs this up with a dedicated hardware button for a stylus-friendly application launcher – much easier to use than the Windows Start menu. The two mouse buttons to the left also give enough control over the more advanced areas of Windows. With the slide-down keyboard, mouse buttons and Vista modification, the UX27 is vastly more usable than the Samsung Q1-SSD, particularly when the latter is separated from its portable keyboard. And the unit sits much more comfortably in the hand than the Q1-SSD.

We were pleasantly surprised at the UX27’s responsiveness zipping around Vista. You’ll get the full Aero interface, with all the transparency effects, and no sign of sluggishness. With a 1.33GHz Intel Core Solo U1500 processor and 1GB of RAM, it’s a big step up from the 900MHz Celeron M of the Samsung. Like the Q1-SSD, our sample Sony UX27 had a 32GB solid-state disk, which should prove far more hardy to the bumps and knocks of constant travel. Unfortunately, only a standard 40GB hard disk will be available on Australian retail models. We also couldn’t reliably benchmark it as our benchmarks still have some Vista-based gremlins.

Initial impressions of the screen itself were mixed. It’s glossy and vibrant, although you may need to increase the DPI settings if onscreen objects seem too small – the 4.5in diagonal packs in a phenomenal resolution of 1024 x 600 pixels. Sony also attempts to overcome this with hardware zoom buttons, although we found these too fiddly.

Like the Q1-SSD, you get 802.11a/b/g wireless and a CompactFlash slot for extra storage or a GPS aerial. Battery life is on a par with the Samsung at around 3hrs in light use. But, with the UX27, you also get a fingerprint reader and front and rear webcams.

While there are a lot of positives for the UX27, there are some significant negatives too – not least the price. The Tablet PC tools make the UX27 functional and lessen the need to use the tiny keyboard, but they ultimately don’t elevate the UX27 much beyond a powerful digital note-taker. It’s also large and heavy enough that you’ll have to carry it in a bag, which means it’s more likely to get knocked, making the one-year warranty look stingy.

We’re yet to find a UMPC we’d feel compelled to buy, but the UX27 is the most appealing so far. But we suspect most people will end up plumping for a far more functional ultraportable.