there is no problem in my main user account, but in other is system font very ugly. Ragged and thin. I use default ubuntu - font - family. The same situation is in LightDM.
I tried delete .fontconfig folder, unity --reset, Ubuntu Tweak and nothing helped.
Screenshot of broken font: http://i.minus.com/ibnxpjNSousCBJ.png
Scrennshot of normal font: http://i.minus.com/iQzXY2eMAiTcY.png