While the cost of desktop computing has been driven down over the course of many years, there's one area that seems unaffected – all-in-one PCs. The nature of the niche these machines fall into means that they never seem to become popular enough to bring the price down.

The Sony Vaio L Series is the Japanese firm's latest stab at this expanding market and it comes in two powerful derivatives – the VPC-L21S1E and VPC-L21M1E – the latter of which we're focusing on here.

The S1E costs just under £1,500, while the M1E is a touch more down-to-earth at £1,200.

A touch of overkill?

The discernible differences between the pair are a Core i7 processor rather than a Core i5 in the VPC-L21M1E, an extra 4GB of RAM (making for 8GB in total) and a Blu-ray writer instead of just a Blu-ray player. Whichever of these machines you opt for, it's a considerable investment for the privilege of owning one.

However, it's one of the more competitive all-in-ones right now. The similar HP TouchSmart is almost identical in price, while Acer's Z5610 comes out pretty close once all the optional bits are added on top of the starting price. The Lenovo IdeaCentre B500 is a little more wallet-friendly at £850, but the hardware isn't anywhere near a match for the L Series.

Sony's line features some neat additions, put there in an attempt to place it ahead of the current all-in-one field. Not only does it have a multitouch screen – which is excellent, with only a fraction of a second's delay when using your finger to flick through photos or pinching and pulling to zoom in and out of them.

It also has a secondary touch-activated control bezel around the display. This enables you to access a variety of everyday functions by touching the surround as opposed to using your keyboard and mouse. It's a novel idea and while technically it seems to work quite well, provided you can remember what the functions are and how to activate them, they're a bit, well, uninspiring.

For example, there's a facility that allows you to go back and forth in a web page by hitting the bottom-left or bottom-right of the surround and an application zoom that's controlled by dragging your finger up and down to the right of the screen.

The screen itself is bright, if a little reflective thanks to an overly glossy surface finish. Pop a Blu-ray movie into the side-loading slot and the L Series produces a solid, crisp picture, which manages to stay smooth even in the most hectic parts of a film.

Blu-rays (or any other disc format, for that matter) are dealt with by Corel's WinDVD software and this is easy to use. It works perfectly with the touch screen, allowing you to flick through scenes with your finger.

The sound is also impressive. Although it'll never rival a decent set of desktop stereo speakers, it's certainly more substantial than the speakers you would tend to find in most TVs or monitors. However, the underside location of the speakers on the PC seems to be a hindrance, because the sound they produce travels down to whatever surface your L Series is on, instead of projecting out towards the listener, which can make them sound a little flat.

Odd design decisions

As well as its touch surround, the L Series features a range of buttons and connectors conveniently located around the edge of the screen for easy access. Most of these are the standard sort of fare that you might expect to see, although there is the odd inclusion of a Web button, the purpose of which is simply to open a browser window. Unfortunately, this is pointless, since it's quicker to just hit the browser icon on the taskbar.

Of infinitely more use is the 'Assist' button located on the left-hand side of the machine. When pressed, this takes you to the Vaio Care page, from where you can check the status of your PC when you think there might be a problem.

One of the L Series' best features is an HDMI input and output, which mean that as well as being able to connect it up to a big screen TV and output the picture, you can also choose to use it as a monitor.

It looks very smart, and although it doesn't quite have the same sort of charm that an iMac does, for example, it would certainly look at home anywhere you chose to put it, provided you don't have an issue with the colour black in your particular domain.

Overall, Sony's latest all-in-one PC is a powerfully impressive and classy machine, but it's expensive and some mind-boggling design decisions have been made, which are likely to hinder rather than help the person using it.

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