Summary: I did a lot of research on ultrabooks before purchasing this exact model. I am very happy with the build quality and system performance. The keyboard is excellent (laid out like a real keyboard, don't buy X1 2nd generation) and the audio is better than you will find in any other ultrabook.
Summary: Have purchased about four of these for work. Nice solidly built, and light notebook. I was unhappy to discover that you can add memory to the system but the user I purchased it for will still be able to do everything they want with 4GB.