Here is the engadget review. It has comparisions to many more ultrabook models than the Ars Technica review does.

http://www.engadget.com/2012/08/14/lenovo-thinkpad-x1-carbon...

There are definitely some compelling Ultrabooks besides this Lenovo. What about the similarly priced Samsung Series 9, or if you have a tighter budger and can accept lower specs, the Toshiba Portege Z935?

http://www.engadget.com/2012/07/06/samsung-series-9-review-1...

http://www.engadget.com/2012/06/05/toshiba-portege-z935-z835...