TouchSmart systems are the elder statesmen of the touchscreen world. HP has had plenty of time to perfect its touchscreens, and first impressions of the TouchSmart 600 are good. It has a 23in, 1920 x 1200 panel, which responds accurately and swiftly, and the proprietary software offers large, finger-friendly links to HP's own utilities and widgets alongside Windows Surface tools.
However, the hardware occasionally struggles to keep up, which results in sluggish animation, and the screen isn't as bright as we'd like, looking dim next to the Sony.
The chassis can't compete either. It may look good, but the glossy plastic finish just isn't as luxurious as the VAIO's metallic chassis. The glossy coat also quickly attracts unsightly fingerprints.
The HP's specification is also second-rate. The mobile Intel Core 2 Duo P7450 processor runs at 2.13GHz and returned a score of 1.10 in our benchmarks. That may look okay in isolation, but in the context of this Labs it's disappointing.
The rest of the internals are better. The Nvidia GeForce GT 230M graphics chip scored 45fps in our low-quality Crysis benchmark and handled 1080p video without fuss, and the 1TB hard disk is generous. There's also a Blu-ray drive, 802.11bgn wireless and a hybrid DVB-T/analogue TV tuner.
But even here the TouchSmart falls behind. The Acer and Packard Bell systems offer similar specifications, aside from the Blu-ray drive, and cost considerably less, and the HP's only rival when it comes to price - the Sony - offers a dual DVB-T tuner and more power.
It's this stiff competition that proves the HP's undoing. Both the Acer and Packard Bell systems are better value, while the VAIO is a more convincing machine thanks to its better design and features. The TouchSmart isn't at all bad, but when others at both ends of the scale are better, there's no reason to settle for it.
The TouchSmart 600 is now end of life, too - the replacment model, the 300, uses an AMD processor and smaller screen.