For all the other differences between Sony's S and Z VAIOs, one of the most significant is the screen. Though it's actually a little smaller than that of the 13.3in S, the 13.1in Z manages to pack in more pixels: it comes with an Apple MacBook Air-matching 1,600 x 900 resolution by default, and £40 extra gets you a whopping 1,920 x 1,080 pixels (Full HD)! Though you'll need eyes like an eagle to use that resolution comfortably on a display this small, it's great to have the option and one of the unique features that sets Sony's top-end ultraportable above the competition.
The display's surrounded by a matt bezel (which also contains an HD webcam) and features a semi-glossy coating, so reflections won't be as much of a problem as on full-gloss examples. Horizontal viewing angles are very good, though verticals still suffer from a significant degree of the contrast shift problem that plagues most TN laptop panels.
Though there is a hint of light bleed from the top and bottom of the screen, backlighting is otherwise even and there are no unwanted artefacts like banding. Colours are vibrant and blacks quite black, though unfortunately contrast isn't all that good, and the 1,600 x 900 display on our review sample failed to distinguish the three darkest grey shades in our greyscale test.
Last but not least, the small dot pitch ensures impressive sharpness, ensuring even the smallest fonts are legible. Overall we would say it is an above-average screen, but slightly disappointing dark detailing means you're still better off with the Samsung Series 9 900X3A if you're looking for a great TN screen. Or you can opt for one of the rare laptops sporting a high-end IPS panel, such as the non-tablet version of the Lenovo ThinkPad X220.
Under its hood the Z is also impressive. Our sample sports an Intel Core i5-2410M. This 2.3GHz 'Sandy Bridge' dual core CPU Turbo Clocks to 2.9GHz and offers up to four virtual cores, and should be adequate for the vast majority of users. And just in case it isn't, you can upgrade to a faster 2.7GHz Core i7-2620M for £180.
It's backed up by up to 8GB of RAM (4GB on our model) and a 128GB SSD as default. The Z is so premium that Sony doesn't even offer the option of a hard drive. Those who want more storage can simply shell out the – wait for it - £1170 that'll net you a 512GB SSD. Needless to say, with faster third-party SSDs of the same capacity costing a mere £560 at retail, you're really paying over the odds here.
When it comes to graphics, the default option is Intel's integrated HD 3000 chip, which will just about suffice for a few GPU-accelerated apps and undemanding games. However, if you do 3D work or are into games, it's well worth purchasing the aforementioned dock with its Radeon HD 6650M dedicated graphics.
As an example of the performance boost you can expect with the dock hooked up, our Stalker: Call of Pripyat score on 720p at medium detail went from an unplayable 15.7 frames per second (fps) average to a smooth 37.5fps average using the Radeon. This is one of the best scores we've seen from an ultraportable, with the VAIO S' HD6470M only managing 23.7fps in the same test.
So yes, gaming is definitely an option on the Z, though there are a number of disadvantages compared to integrated solutions. For example, you'll need to be near a power outlet to feed the dock. Disconnecting the dock, meanwhile, requires you to exit any applications using it and press a physical disconnect button, otherwise your laptop will crash when you unplug it. And of course you'll need to carry the dock around with you if you want to game while away from home.