I've had the opportunity to play with X1 Carbon not too long ago and found it to be pretty damn impressive. Haven't used it with linux, but if I was to get a high-end laptop, I would definitely get an X1. Nice to see that it's also linux-capable.
It looks well, feels well, but it's not suitable for devs. I'm a long time lenovo x200 line user, and the X1 is really bad compared to those models.
Can't recommend.