Have you tried it in Elite: Dangerous?
No, I haven't played Elite in a couple of years but I might download it again and try the Tobii Eye Tracker in it. From the comments I've seen on the forums and other community sites, it seems to be implemented very well. It really does depend though on the developer side of things, on how they implement the eye tracking in the game. I know the studio I work for works very closely with the Tobii guys and have implemented in a lot of our games like the Hitman series, Deus Ex and Final Fantasy XV.