I just got a brand new Dell XPS 13 9360 and replaced Windows with Ubuntu 16.04.1. Everything seems to work out of the box, except for few issues with video output to external monitor.
I bought two adapters from Aukey: USB-C to VGA and USB-C to HDMI. The first one is working flawlessly, but HDMI one has few issues.
My usual monitor is a 24" FullHD Samsung TV monitor: when I connect it through the adapter, audio is working fine but it looks like that colors are rendered with a 16-bit palette, thus making it unusable (I tested the adapter on Windows before wiping it and it works correctly).
I tried on another Samsung TV monitor with the same issue.
I tried also on a Toshiba TV and it works correctly all the time, so there must be some issues specific to Samsung displays and Ubuntu when using USB-C adapters (the same display had no issues with my previous computer running Ubuntu).
The only workaround I could find is to turn off Samsung TV monitor, connect it to my XPS and then turn it on: in this case it works correctly. But after unplugging, if I want to plug it again I have to turn monitor off and on again.
For the moment I can live with this, but I was wondering if anyone had the same problem and found a definitive solution.