I own a 2015 Dell XPS 13 Developer Edition, which is a truly fantastic laptop. A quick product review: I recently purchased the Dell USB 3.0 Triple Display UltraHD Universal Dock (D3100) in order to help me use my laptop more effectively as a desktop replacement at work.
I bought the dock mostly because of the promise of being able to use 2 monitors with my laptop. The dock worked fairly well and it looked elegant. It replaced an Amazon Basics 7 port USB 3.0 that I had previously bought.
However, getting monitors set up was not easy. I attached two, year old 1080p monitors. They were, eventually, auto detected, but I had to reboot the computer several times to get them working, even after installing the drivers from DisplayLink.
But the worst part - using the monitors used 50% of my entire CPU speed. It seems that the display-over-usb-3.0 works by compressing video for sending on the CPU; in any case, I obviously could not afford to constantly use one full CPU core just for my monitors - and monitors that caused the mouse to flicker on the laptop screen, at that.
This is an issue that has been reported widely, so DisplayLink should have gotten a fix out already - and apparently, it might be ameliorated on more recent versions of Ubuntu. But the bottom line is that the Dell D3100 does not work out of the box with the XPS 13 Developer Edition - would not recommend.