Whatever the reason for the delay, which ideally would have involved fixing the freezing problems suffered by many users in the US, we got our hands on the high-end productivity machine to see whether it's a deserving alternative to Microsoft's Surface Pro 4.
One of the drawbacks of Microsoft's hybrid design, where the display is a removable tablet, is that most of the components are housed behind the screen. This leaves the Surface Book feeling a little top-heavy, although the whole thing still weighs a decently light 1.51kg and at 312x232x22.8mm it's nice and slim as well.
The 'dynamic fulcrum' hinge is a nice touch as well, folding outwards in segments rather than rotating on a pivot. The display is held is place with extremely strong magnetic clamps, easily the most secure we've tested on a convertible, and can be flipped around so that it faces outwards in a stand or tent configuration.
However, unlike Lenovo's similarly unfurling 'watchband' design, the Surface Book's hinge doesn't allow it to close completely flat; only the very top tip of the tablet segment comes in contact with the keyboard. This leaves a gap which, slightly worryingly, shows how the tablet can flex slightly when pressed.
This was a bit surprising because the Surface Book is otherwise very well built. It uses a durable magnesium chassis similar to the Surface Pro 4, and includes a powerful magnetic clip for the Surface Pen, a comfy backlit keyboard with chunky-feeling, deep-travelling keys, and a workable mix of ports including two USB 3.0, an SD card reader and a mini DisplayPort. All of these are located on the side of the keyboard, rather than the tablet, so the latter can't really be used without the former to hand, but since this is fully intended as a laptop device that's fine.
The Surface Pro 4's outstanding screen was one of its biggest assets, and the same is true of the Surface Book. In fact, the 13.5in, 3000x2000 panel is even higher-res than that of the Surface Pro 4. This doesn't really make it noticeably sharper, but it provides utterly superb detailing and smoothness.
Microsoft's laptop also manages to balance the colours well, showing punchy and vibrant reds, greens and blues with none of the sickly pop of an oversaturated screen. It's bright, too, which helps cut through the reflectivity of the glossy finish.
The Surface Book has been built with graphic designers and illustrators in mind, and beyond the bundled Surface Pen nowhere is this more evident than in the excellent display.
Operating system and software
Windows 10 Pro, the upgraded, more business-friendly version of Windows 10 Home, is Microsoft's OS of choice for the Surface Book, and it's a good decision. Bonus BitLocker encryption makes Windows 10 Pro more secure than the basic edition, and if the screen is removed to be used as a tablet the Continuum interface can automatically adapt the UI into a more touch-optimised layout.
Microsoft also seems to have kept pre-installed apps, beyond what's included with Windows 10 Pro by default, to a minimum; there's far less bloatware on the Surface Book than manufacturers like Acer, Asus and Lenovo include on their laptops.
We tested a top-spec model with an Intel Skylake Core i7-6600U processor, plus the maximum 16GB of RAM and a discrete 1GB Nvidia GPU in the keyboard. It was as fast and responsive as one might expect from the specs, right up until it suddenly and completely froze.
A nearby Microsoft rep said that we were actually using a late pre-release model dating from January - late enough that the hardware had been finalised, although evidently early enough that not all of the software problems had been ironed out. Even so, it's not terribly encouraging that Microsoft has struggled to get its own OS and hardware to work together reliably so close to the launch date.
This is a particular shame as, when it does work, the Surface Book performs beautifully. Opening multiple windows doesn't cause slowdown at all, and even high-demand 3D modelling apps like Adobe Fuse CC run quickly and smoothly, making the Surface Book a viable desktop alternative.
Microsoft's first foray into the laptop market is confident and, dare we say it, largely successful. It's particularly impressive that a dedicated GPU has been squeezed into the slimline case, even if gets taken out of action when the display is removed from the keyboard. The screen is absolutely among the best we've used and, with all these premium features, anyone could be forgiven for rushing out and buying one.
However, we think the best course of action, even if you're outright smitten with this magnesium hybrid, is to wait. We are not convinced that the Surface Book is reliable enough for professional use, at least for the time being, and holding off until a price drop could save huge amounts of cash. The model we tested, for reference, costs a heart-stopping £2,249.
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