The Ubuntu Mate OS works very well on the Pi so is well worth a try. If you have Mate 15 already installed and want to update to the recently released Mate 16 you’ll be glad to hear that is a very simple process.

To Upgrade:

Open a terminal session

type: sudo do-release-upgrade

Answer y to the prompts.

NB: This is a lengthy process so once you’ve answered the upgrade prompts you can go and do something interesting!