I could never click a button in the cockpit because it jittered around too much when you leaned into it for a close-up view. It does track a little slower than Track IR, but not bad at all, IMO. I also had to constantly "fiddle" with it, which got on my nerves.
I had it for three weeks,then sent it packing, and returned to my TIR5 with a reflector clip on a baseball cap. I might have kept it, if it wasn't twice the cost of a TIR5, to play with it a little more as the hardware itself seemed well-made.
I also think, and this is just my opinion, that "eye tracking " is just a gimmick to sell head trackers. I couldn't find a real use for it anywhere in any eye-tracking app or game. Not without a huge cost for much better eye-tracking hardware. Tobii doesn't have the ability.