It is a flexible rig that is very expressive and easy to use. Each eye is separately scalable as well as the main control. It has been carefully tested for errors and makes no double transforms or other rigging problems when animating It also come with a Mental ray IBL setup with HDRI image included. I made this for character set up - just import it and constrain it to your character.
I built this rig in maya 2012 for those who don't have the newer Maya.