I recently bought Dell xps 13 9350 with qhd touchscreen (developer edition is not available in my country) and did reinstall to Ubuntu Gnome 16.10. I encountered boot issues.
Issue is with boot time. During the boot there is for at least 10/15 second some gray screen which then dissapears by "rolling" up and boot continues normally. First appears Dell logo, then gray screen, then loading screen. Also I can't see GRUB menu.
Because of that boot takes around 25 second what is unbelievable time with specs like mine, old docked thinkpad is faster than that. I found out it could be GRUB but even by setting it's time to 0 it didn't help at all. Even boot log thinks it takes 8 seconds for OS to boot. I also tried Unity/Elementary OS/Fedora and boot times were acceptable.