I've had two laptops that I've installed Ubuntu 12.04 on and both have worked great. One was a Dell Vostro V131. Literally everything worked and it had such an amazing keyboard layout. It was so hard for me to give it up. I upgraded earlier this month to an ASUS Zenbook UX302LA. The only things that didn't work out of the box was WiFi and the brightness keyboard buttons, these were quickly fixed with using a back port module. I put an extra 8GB of RAM and a 256gb SSD and the things flys. It also has a Haswell CPU so it gets about 9 hours of battery life.