Along with full x86 compatibility, one of the alluring features of Microsoft's Surface Pro 3 over an iPad or Android tablet is its strong performance. You can get a lot done with a dual-core Intel Core i5 processor, 8GB of memory and an SSD of up to 256GB – but in a tablet form factor, not a laptop, so it's portable as well as powerful.
The ThinkPad Helix takes this one step further, offering even greater performance under the hood. Part of this is down to it using the latest generation of Intel processors – the 14nm Broadwell-based Core M chips.
Unlike the Surface Pro (and certain other Windows tablets), which is a traditional tablet with an optional Type Cover, the Helix is a true 2-in-1 hybrid tablet, with a dock called the Ultrabook Pro Keyboard that features a proper trackpad with physical buttons, and an array of extra ports.
It joins a number of other 2-in-1 Windows tablets in offering high performance x86 compatibility. The Dell Venue 11 Pro 7000 uses the same processor, while Lenovo's own ThinkPad Yoga 12 has a Core i5 processor rather than a Core M.
As it carries the ThinkPad branding, the Helix has a few of its trademark features. Namely, a red joystick right in the centre of the keyboard dock to move the mouse pointer, two chunky physical mouse buttons and, when the tablet is woken from sleep mode, the dot above the "i" on the ThinkPad logo lights up red.
Since ThinkPads are business-class machines, the three ThinkPad Helix variants carry business-class pricing. Starting at £1000 inc VAT ($1241 in the US, or AU$1602) and going up to £1500 inc VAT ($1860 in the US, or AU$2400) the Helix is certainly no toy.
Although the Helix is an 11.6-inch tablet, it feels quite hefty compared with the Surface. When it's docked and closed shut, it isn't completely obvious which side is the front and which is the back, since the hinge completely covers the front edge.
It's not especially thin either. With the dock closed it measures 22mm off the ground, with the tablet portion measuring almost a centimetre. It matches the Surface Pro in terms of weight, starting at 795g (for the tablet on its own, since the dock increases the overall weight to 1.35kg).
There's a black bezel around the display, which seems thick, measuring 20mm at the sides and 25mm at the bottom, with the effect of making the viewable screen area look a bit like a letterbox.
But the ThinkPad range has never been known for form over function – and a rigid, solid design adds a feel of sturdiness. We wouldn't test it, but it does seem like the Helix could survive a few light knocks that might easily destroy other tablets.
The tablet and dock are separated by pushing in a button at the side, otherwise they're bonded together very strongly.
Holding the tablet in your hand, the device has an odd asymmetrical look. One edge uses round corners, while on the other the corners are square, for a flat connection to the dock.
You can flip the Helix around to use it in an upright position, with the keyboard behind it, or push it down again so it becomes more of a 'slate'. And if you want, it can be used in 'tent' mode, like an inverted V shape, although since the dock works so well to hold the Helix upright, it's hard to see why you'd do this.
There are plenty of expansion ports. On the tablet, a USB 3.0 port hides behind a protective cover, joined by a second USB 3.0 port on the dock, along with a DisplayPort output. And behind another protective cover on the tablet you'll find slots for a microSIM for mobile broadband, and a microSD card.
At the top of the tablet is the power switch and an autorotate lock button, with a volume rocker and 3.5mm audio jack at the side. Further down you'll find a microHDMI port.