Rather than employ some kind of bizarre convertion mechanism to bring tablet functionality to a laptop -- like the Dell XPS 12 or Lenovo IdeaPad Yoga 13 -- the S400 simply whacks a touchscreen into a regular laptop.
You get to enjoy the gestures and live tiles that make up the colourful Windows 8 operating system, switching easily to the keyboard when you need to get on with some typing.
There's a powerful Intel Core i7 processor stuffed inside, along with 4GB of RAM and a 500GB hard drive. That lot will set you back a reasonable £700 from PC World. If that's too pricey for you then there's a Core i5 variety for £100 less, but naturally you can expect a smaller helping of power.
Should I buy the Asus VivoBook S400E?
The S400E packs a potent Intel Core i7 processor with 4GB of RAM that I found to be extremely powerful. It matched the performance of Acer's Aspire S7 -- a laptop that costs more than double the asking price of the S400E.
That engine is protected by a sturdy metal shell with a black, brushed finish. It's not super-attractive but it's functional and will keep it protected on the road. For the money, you'd be hard pressed to find something more rugged.
The responsive touch-enabled display helps navigate around the gesture-based Windows 8, but it's let down by its poor resolution and disappointing colours.
If you're after a great display for getting the best out of your movies, take a look at Sony's Vaio E Series 17, or the Dell XPS 12 if you want a portable touchscreen Windows 8 laptop.
For general computing on the move, however, the S400E offers a good all-round set of features for a reasonable price.
Design and build quality
The S400's shell is constructed primarily from metal, and has a deep grey/black lid. It's far from an exciting look, but the brushed effect Asus has given it saves it from being yawn-inducingly dull. At the very least it looks functional -- I wouldn't hesitate to pull it out in a meeting -- although it's not likely to catch the eye of anyone in the coffee shop.
That black lid is an absolute magnet for fingerprints though. You'll want to keep a polishing cloth of some kind handy if you want it to maintain its professional look. Aside from this, the design is very much par for the course. Silver metal is in abundance under the lid, and the bottom of the machine is clad in black rubber. The keys are set directly into the base -- there's no separate keyboard tray -- which, together with the edge-to-edge glass of the screen, help make it look more expensive.
It's 339mm wide and 239mm deep so it'll fit into an average backpack without too much pushing and shoving. At 21mm thick, it's considerably thicker than its Zenbook UX31 cousin, but it's not exactly what you'd call fat. It weighs in at 1.8kg, so you're unlikely to feel too bogged down if you have to carry it around for a couple of hours.
The metal shell makes it feel particularly sturdy. There's minimal flex in the lid and none at all in the wrist rest. The hinge too feels sturdy and doesn't bend when opening. It's quite stiff, but it needs to be in order to avoid falling down when you're using the touchscreen. It certainly feels burly enough to put up with a few knocks inside a rucksack, so don't hesitate to take it down to Starbucks.
Around the edges you'll spy one USB 3.0 port, two USB 2.0 ports (a shame that not all USB ports are of the faster 3.0 variety), an SD card reader, Ethernet, VGA and HDMI out, as well as headphone and microphone jacks. Storage is taken care of by a 500GB hard drive.
To help you get the most out of Windows 8, the S400's 14-inch display has been made fully touch-enabled, letting you use the various gestures and poke at the live tiles that make up the backbone of Microsoft's colourful new OS. It's particularly responsive and thanks to the stiff hinge, very comfortable to use.
Sadly though, Asus hasn't bothered to pack it full of pixels. It offers a rather unimpressive resolution of 1,366x768 pixels, which is the absolute minimum I'd expect to see on a machine of this size. It might be a fairly affordable laptop, but I'd have liked to have seen at least 1,600x900 pixels. Asking for Full HD at this price might be a bit of a push though.
Icons and tiles look pretty sharp, although small text on Web pages doesn't have the same clarity you'd find on Full HD displays like Dell's XPS 12. It also means you won't be able to fully enjoy 1080p video, so don't bother hampering your internet connection with YouTube clips above 720p.
Unfortunately it doesn't really make up for the lack of pixels in image quality either. It's not particularly bright, which doesn't help cut down on reflections, and colours and contrast didn't impress. It's fine for most everyday tasks, but if you want to really enjoy your favourite movies on the go then it's worth at least getting an eyes-on before you drop your wad.
Power and performance
Slapped inside that metal jacket you'll find an Intel Core i7-3517U processor clocked at a spritely 1.9GHz along with 4GB of RAM. That's a decent set of specs for the price, punching above the Core i5 chip found in Dell's XPS 12 and knocking a few hundred quid off the price too. You'll find the same specs inside Acer's slender S7 which comes in at a whopping £1,500.
To see how it stacks up against the competition I booted up the Geekbench benchmark test, on which it was able to achieve a score of 7,693. The S7 racked up 8,257 on the same test which isn't much of a difference and it managed to edge out the XPS 12's score of 7,223.
It was able to encode my 11-minute 1080p video file into 24fps H.264 format in 11 minutes and 30 seconds, which isn't bad at all. The S7 took the same time to complete the task, so it seems that the two are well matched in power-wise. In terms of raw performance, the S400 offers better value for money.
The S400 coped well with image editing in Adobe Photoshop Lightroom 4 too. Large high-resolution images imported quickly and there was minimal delay when switching into the Develop mode. There was barely any lag between moving settings sliders and seeing the effect take place, which helps make fast editing that bit easier. Similarly, it was able to export my 11MB image file in around 3 seconds, significantly beating the 1 minute it took the HP Envy x2 to export a 2MB file.
That Core i7 chip appears to really take its toll on battery life. When I ran a high-definition video loop until the battery conked out, the S400 managed to keep going for just under three hours.
Playing back HD video is more taxing for the computer than working on office documents, but it's not massively demanding. If you were really pushing it with heavy multi-tasking including playing videos, Web browsing on Wi-Fi and keeping the screen brightness on max then you shouldn't expect more than a couple of hours life.
That's not a great time -- you won't be able to get a full day's use out of it unless you're extremely careful what you do. Keep the brightness down and switch off wireless networking unless you absolutely need it. Even then, I'd recommend keeping the plug with you if you really need to get on with work.
The Asus S400's Intel Core i7 processor puts on a good show, tackling the most demanding of tasks without argument. The metal shell might not be particularly pretty, but it's sturdy and helps give it a more expensive feel than you might expect for the relatively reasonable price.
The responsive touchscreen is extremely handy for getting the most out of Windows 8, but it's sadly let down by an unimpressive resolution and lacklustre colours.
If you're after a Windows 8 laptop for work on the go and don't want to spend the Earth, the S400 is a very good option. If your priorities lie in enjoying the latest high-definition movies on your travels and you're not fussed about the touchscreen, you can spend your money more wisely elsewhere.