Microsoft Surface runs Windows RT in its purest and most vanilla form. Windows 8 doesn't have the capacity for skinning that we've seen on the likes of Android, although we wouldn't put it past some manufacturers to add their own awful overlays.
If you're not familiar with Windows 8, let us give you a quick synopsis. Windows 8 and Windows 7 are essentially identical, except that the Start menu has been axed in favour of a Start screen, a giant colourfully-tiled HTML 5 overlay, through which everything must be run.
You can drop back to the traditional desktop, but without the Start button, you'll find it extremely limited.
The Start-screen menu is a big jump even for the most experienced Windows user, but it doesn't take long to show its worth, and it's clear after a few hours of use that it's intuitive, beautifully designed and solidly built.
The big tiles, which push information such as new emails and news headlines to you, are super touch-friendly, which is perfect for tablets such as Surface, and can be moved around to create a custom mix not only of apps, but also pin contacts, books, movies and more.
The only criticism of the Start screen is Windows 8's appearance of 'my first PC', and power users are the most likely to bemoan its introduction.
The same back end is present, but to access it one must use the search charms from the right-hand corner.
Of course, there are already hacks and workarounds to restore Windows 8 to its normal state, but for touchscreen devices like Surface, this would be a disaster.
A common misconception is that the traditional desktop isn't available in Windows RT, but that's not true; it's accessed via the desktop tile on the Start screen, but its relevance is severely diminished.
As Windows RT can't run traditional programs you need to use the old style Windows Explorer less, but it's still on hand for browsing file systems, USB sticks, organising folders and more.
The 'charm' bar to the right also includes search and share buttons and these are threaded through every part of the OS, from files to settings, to the information held within apps.
Another triumph is the on-screen keyboard, which is large, sensitive and easy to use. It's not as smart as some third-party keyboards on Android, but we typed with two hands quickly and accurately and the extra inch of screen space made it much easier to use than its iOS counterpart.
We had a few problems with the large keyboard panel blocking information we needed, but the icon to show or hide the keyboard is always on hand in the bottom-right corner of the desktop.
As we've already mentioned, performance is a slightly mixed bag. The system is always responsive, with silky smooth transitions and snappy navigation.
However, we found that some apps were slow to load, with lingering splash screens. What's more, 1080p playback was a few frames per second short of perfect.
While we wouldn't say that the Tegra 3 chip performed appallingly, there's certainly no headroom, and it seems to be the graphics core that struggled most.
Multitasking apps never missed a beat, but it was loading the graphically-intensive apps and movies that showed the biggest strain on the processor.
Even some basic games ran at a noticeably low frame rate, so it seems that Windows RT might need some optimisation.