I've purchased one two months ago, and it's great. Ubuntu worked out of the box (the only exception being the fingerprint reader), and it runs smoothly. The screen is sharp, and it's super light. I'm happy with mine.
I came from a 15” Macbook Pro, and at first it felt a little smaller, but now I am more than used to it such that I can’t even remember what it was like to code on the 15.
I do spend most of my time on my laptop in bed with my knees up though, so the laptop is closer to my face.
That being said, I love my XPS 13 with Ubuntu. Battery life is good, everything just works, build quality is high, and the screen is beautiful (I got the 4k one and run it at 200%).
I won’t be going back to apple ever again (and I used them for 13 years). I feel much more at home in linux.