Calibri sucks. Open Office default fonts are bad on a good day. Adding support for the core MS Fonts is really easy and definitely worth the two minute effort.
Simply open a terminal and type:
sudo apt-get install msttcorefonts
This will install all of the MS fonts that are available in Microsoft Word for you to use in Open Office!
If you are using OpenOffice, restart it and you can finally use Arial instead of Calibri (Thank God!).
