Six years ago I bought an Inspiron 14 that Dell sold with Ubuntu. A few weeks ago I got an XPS 13, the model Dell now sells with Ubuntu (although I didn't purchase the developer version because it had a longer shipping time and I needed it ASAP). Unfortunately, even on this "reference" hardware there are many frustrations.
I installed 64-bit Ubuntu 13.04. Supposedly all of the special tweaks Dell makes to the version of Ubuntu 12.04 they install on the developer edition are included in 13.04. At first, I was unable to boot the installer; I had to switch the boot mode to Legacy from UEFI. Graphics don't work at the login screen; you have to switch to another virtual console and restart LightDM or just enable automatic login. Adjusting the display brightness doesn't work. If I connect it to my TV, X locks up until I disconnect it. Some of Unity's multitouch gestures work, but some don't. I haven't found any way to configure the touchpad; I'd really like to be able to middle-click.
Today I hooked up my Nexus 4. Rhythmbox, Ubuntu's default media player, sees it as an MTP device but locks up and crashes if you try to transfer any music to it. I switched my Nexus 4 from MTP to PTP mode and fired up Shotwell, Ubuntu's default photo manager. It saw the Nexus 4 as a camera but reported an error and failed when I tried to import my photos from it. At least I can transfer files to and from it using the file manager, but if I try to open any files without copying them to my computer first, it fails.