Which one would you get?

It is time to get a new laptop, and I would like it to be as light as possible subject to having a full-size keyboard and a not-too-small (at least 12”) display. So it is down to the MacBook Air versus the Lenovo X300.

I have been planning to move to OS X, and I appreciate superior design, so the MacBook is the default choice, but I also like to be able to connect a computer to other devices, which leads to the problem described in the video.