Toshiba Portege M200

No-one is more committed to the tablet PC cause than Acer. It's already on its third-generation device while others are only just reaching second base, and big names such as IBM and Dell are yet to release anything using the Tablet OS. The C300 series - represented here by the C302XMi - is its latest attempt to bring the tablet PC into the mainstream. Toshiba has a similarly lengthy record as a tablet PC manufacturer, being one of the original gang of three at the official launch of the OS. The consensus there was that it had the best machine - except for the price.

Time seems to have proved us right, because within a year Morgan Computers - retailer of end-of-line and surplus computing goods - was selling them for £1,000, and the entire stock shifted in the time it takes for a bargain rumour to do the Internet rounds. You might expect that both manufacturers would have learned important lessons along the way, and there's no doubt that the latest machines are the fastest and most feature-packed to date.

Given the obvious differences between the two machines, they have a surprising amount in common. Acer has dropped the side-mounted screen-release catches and slightly flimsy swivel mount, opting instead for a chunky and solid design stunningly similar to that sported by the Toshiba. Both are proud carriers of the Centrino badge and consequently boast good performance and respectable battery life. And both come carrying every connectivity option under the sun, including 802.11b Wi-Fi and Bluetooth. But that's where the similarities end.

Acer has taken the odd decision to go large - very large - and in return squeeze in a 14.1in screen. While this makes for a nice display area, albeit at just 1,024 x 768, it adds to both bulk and weight. With the optical drive in place, the TravelMate weighs a hefty 3kg, which is a whole 1.25kg more than the Electrovaya Scribbler SC-500 (see issue 112, p56). But possibly worse than the weight is the awkwardness. Its size of 326 x 272 x 35mm may be fine for a laptop, but it's very unwieldy in slate mode.

Admittedly, you get a well-specified machine. The 1.6GHz Pentium-M is no slouch and is kept company by 512MB of PC2700 RAM. The 60GB hard disk is equally generous, as is the DVD writer that brings DVD-R and -RW support to the portable party. There's also an innovative light sensor that adjusts screen brightness according to the environment, which worked well during our testing.

We were also impressed by the TravelMate's battery life, with a one-and-a-half-hour rapid charge providing a whopping four hours, 40 minutes - and that was with Wi-Fi turned on. With Wi-Fi switched off, it managed to scrape over the five-hour mark. This is twice as much as the previous C111TCi. The only problem for Acer is that even this pales into insignificance next to the Scribbler's nine hours.

But there are other more important problems for the TravelMate. Small things, such as the latch that has to rank as one of the most awkward designs we've ever encountered. Even after using this tablet for a few days, we still couldn't figure out how to get it to shut and lock first time. Then there's the heat, which makes the TravelMate simply too uncomfortable to hold - a notable problem for a laptop, a disaster for a tablet.

So what about the Toshiba? Well, the 12.1in screen seems tiny next to the Acer's, but it looks much better. In fact, Toshiba has produced one of the most crisp and bright screens any tablet PC has sported, and it runs at a beautiful 1,400 x 1,050 courtesy of the nVidia GeForce FX Go5200 graphics. The form factor feels smaller than its actual 295 x 250 x 33mm dimensions, and the 2kg weight is acceptable for a convertible of this size. The only thing spoiling the handling of the Toshiba in slate mode is the heat build-up over a relatively short period of time.