There are a lot of them at CES 2013, but is this the Windows 8 convertible Ultrabook you’ve been waiting for? Built using the same innovative design as the Yoga 13, the IdeaPad Yoga 11S’s screen flips around a 180-degree axis, allowing you to use it as a full-powered laptop when you want it and then move to tablet mode in a single, slick movement.

What’s more, it means you can put the Yoga 11S in movie-watching mode by twisting the screen round and then resting it on the edges. If you don’t see what I mean, the photo below makes it obvious.

The disadvantage? When in tablet mode, your fingers will be touching the keys rather than the smooth surface we’re all used to. For some people this may be a deal-breaker, but I can see what the Lenovo spokesperson means when he says: “At first it’s an issue…but then people get over it.”

In reality, probably the biggest issue for the Yoga 11S when considered as a tablet is its weight. You don’t want to hold a 1.4kg tablet in a single hand for long, so this is a “tablet” that’s better suited to sofa use where you can also rest it on your lap.

But as is becoming increasingly clear as time moves on, there is no “perfect” design. You have to compromise somewhere, and it could be that the Yoga 11S’s many other attractions outweight its drawbacks.

For a start, this is a full-on Ultrabook, with a Core i5 processor most likely to be inside when it launches in June. Add SSD storage and you’ve got the base of a machine that will power you through any work you need on the move.

I couldn’t possibly review a Lenovo laptop without mentioning the keyboard (a traditional Lenovo strength), and again this is a fine example. ThinkPad owners of old might mourn the loss of the old-style keys, but there’s plenty of travel and bounce.

The display itself is another plus, thanks to the IPS technology keeping images vivid and ensuring a generous viewing angle. Sure, a 1,366 x 768 resolution isn’t the biggest, but it’s fine for an 11.6in screen.

When considered as a laptop, the 1.4kg weight also starts to look quite reasonable. Lenovo quotes dimensions of 298 x 204 x 17.2mm, with the key one being that 17.2mm thickness. This will slip easily into your bag.

You might want to find room for a power supply, though, with six hours of quoted battery life. It’s okay but not spectacular.

As with the Yoga 13, Lenovo will be selling the 11S in a fetching “clementine orange” colour – I also got my hands on a dashing pink version (see above), but that will never see a PC World shelf. More sober buyers can opt for a bog-standard grey.

With another five or six months before PC World sees any samples at all, there’s plenty of time for rivals to bring out lightweight convertible Ultrabooks, so I’m not convinced this will be the best machine out there at that time. And for pricing, all we have is the cost of a Core i5 US version: $799.

But that clever hinge and a great keyboard mean it’s a definite contender for anyone who wants a powerful machine to keep them company on trips – it can work during the day and entertain at night.

Core specs

• Up to Core i7 processor
• Windows 8
• 1.4kg
• 11.6in IPS display
• 1,366 x 768 resolution
• Up to six hours battery life
• Up to 256GB SSD storage
• 720p camera
• $799 price for Core i5 US version