I have just installed Ubuntu 15.04 Vivid Vervet (+restricted extras), and noticed that I didn't have to install p7zip or p7zip-full to work with .7z files.
As far as I can see it is libarchive13 that is responsible for giving File Roller the ability to work with the 7z format, but is it still advisable to install p7zip or p7zip-full?
dpkg -l | grep p7zipterminal command there. – Pilot6 May 25 '15 at 12:00libarchive13has some limitations for 7z format. – Pilot6 May 25 '15 at 12:07