Thank You for mention Gaze Point GP3 I will also consider it, even it’s quite big difference in cost.
Deliver time isn’t so important in UX research (I’m aiming on web GUI optimization) unless it’s a live streaming study, where delay have huge impact on output. Since after study you combine raw data with recorded screenplay, similar to films with delayed sound you can easily adjust it, you just need good synch points, EyeX accurancy is far for Touch-Like specially on high resolution, farer from middle of the screen the bigger mistakes (evenmore then 2 cm near the end of the screen), but it’s normal for mostly eyetrackers. Almost 10 years ago I was working on my own software for eye tracking, I used two good quality webcams (HD/60 fps) and infrared lights, based on OpenCV Intel library. Now I would like use this technology in my work :-).