The Guardian has reviewed the Sony VAIO UX1XN and found that though a wonderment of design, it is somewhat fiddly to use.
But delightful though this notebook is to look at and hold, it’s too flawed to be anything other than a novelty.
The review also mentions issues with the keyboard and the tablet input, which I both agree with.
… there’s the first disappointment – the keyboard. You wouldn’t want to do much more than tap out an email on it, as the size of the keys make it no good for touch-typing. Double-thumb input is feasible, but the tiny keys make it hard to be accurate.
and
The touchscreen is a nightmare. Fiddly to calibrate, it failed to retain its settings and eventually refused even to acknowledge that it was in fact a touchscreen. So I resorted to the pointing device.
I still think it is useful and not as flawed as the review makes out, and the more I use it, the more uses I find for it.