The beta version of my excellent Dell Sputnik (XPS 13) wasn't quite cutting the mustard for some side freelance work I'm doing since it only has 4GB of RAM, but I loved the machine so much I opted to get its big brother, the XPS 15. Specifically I got this model, and yes since I needed it pronto I actually bought it in person at the Microsoft Store in Bellevue, WA. I'll always hate myself a little for going to a Microsoft Store but it was darn handy to have one nearby and just go get the new machine as opposed to waiting to have one shipped.
When I got it home I didn't even boot into Windows 8.1, I just stuck an Ubuntu 14.04 USB stick in the machine and installed that. The only trick to installing Ubuntu is you have to go into the BIOS, turn off Secure Boot, and turn on Legacy Boot Mode.
Once Ubuntu is installed everything works out of the box. The screen runs at the full, mind-blowing 3200x1800 resolution, and even the touch screen works. No issues with sound card, WiFi, or anything else. Awesome.
The only annoyance is the default settings for the Synaptics trackpad are a little jumpy. OK, more than a little jumpy. Luckily with a bit of research I found an easy fix that definitely did the trick for me. Basically you just need to change the FingerLow and FingerHigh settings to reduce the sensitivity and the cursor jumps around no more. I used the settings in the link but you can adjust as needed if those specific settings don't work for you.
Only remaining thing to figure out is what to do with this ridiculous amount of screen real estate. Couldn't be more pleased with this laptop!