So, I tried the new 15.0.1 version (Ubuntu 15.10) with Office 2013. It installs fine, the apps start up normally.
Unfortunately the functionality is heavily limited:
Word: (3 Stars)
- seems to do ok with new documents
- opening and editing documents also works ok
- it's terribly slow.
- some UI elements are not quite at the right place (especially in the save/open dialog)
- fonts rendering is somewhat jenky in places
- PDF export does not work
Powerpoint: (2 Stars)
- does not let me click on stuff in the main section, can only draw selection-rectangle
- Crashes when clicking "File"
OneNote: (1 Star)
- Refuses to start, wants me to install something called Desktop Experience feature
Access & Excel: (4 Stars)
- Everything seems to run fine in acceptable speed
- Sometimes crashes on me saving stuff
- some UI elements are not quite at the right place (especially in the save/open dialog)
Publisher & Outlook (2-? Stars)
- Starts and stays up
- not much tested, tbh
Lync (1 Star)
All in all: Some stuff works, unfortunately, the one thing I would need the most (Powerpoint) does not... I think it's a step in the right direction, but still a long way to go.
//edit: Added the information that I was using the Linux version of Crossover under Ubuntu 15.10