I really like the design of the ZBook15. With its black and grey colours it looks much better in real life then on photos or videos. The keyboard is the best I`ve ever typed on. I have an Elitebook 8570p at work and the keyboard is also great but the ZBook 15 keyboard is quite better. But the previous Elitebook models look a little more solid to me.
The Full HD screen is ok – not more or less.
Usually the fan is always on at minum level even while web browsing. I use the notebook fan control tool to manage the fans and no it is silent while office work.