I have a ThinkPad X1 carbon and it's crap. At least running Ubuntu on it is garbage. Battery life is terrible, sometimes the screen flickers which I suspect is video driver, suspend doesn't work and locks up the machine. Had to return 2 of them due to hardware issues when we ordered one for everyone on my team. I like the portable form factor, display, keyboard. But stability/usability has not been the best experience. Which is strange because the thinkpad are often well behaved when running Linux.