* Graphics card glitches - I paid close to 4K so I don't have to deal with quality control issues.
* Touchpad is just too large. I found myself resting my palm on it all the time, and sometimes (clicking) without realizing it. Also, if you like lying down and working (which I do sometimes because of a lower back problem) the size of the touchpad will make you work extra hard to avoid accidental clicks.
* Had the machine for ~ 10 days, used the touch bar less than that. Definitely not worth the money. Hopefully in the future, they'll have the 15' option without it.
* The bootcamp experience just sucks (this was my primary reason for returning it). Currently, there's no way to gracefully switch between discreet and integrated gpu, so the battery life is terrible, like two-and-a-half-hour maximum battery life terrible. gpu-switch doesn't work either. In fact, if you use gpu-switch you'll have to rebuild both macOS and Windows as the machine will just hang when you try to boot into either.
* Recovery mode has many issues with network connectivity. A few times, I had to tether/connect to my iPhone hotspot for it to go through.
* Sharp edges everywhere.
The specs are very underwhelming too, but I was willing to tolerate lower specs for higher build quality. I actually just picked up an XPS 15 9550 from Microcenter. Got the 2.6Ghz, 16GB (expandable to 32GB), 512GB SSD, 4K touchscreen for $1350 (an open box, new for $1499).