You make it sound like Trackir doesn't work in AC......which is simply not true.
You can use ANY profile within TIR's collection of profiles and the device will work beautifully.....You can also make a profile called anything you want to call it, and when you open TIR just select that profile and then start the game.....the game will detect TIR automatically and when you load up a car
it will work.
I haven't tried any of the less expensive options for head tracking so I cant comment on how they compare...I have read that they really are not as good??....But I can tell you that Trackir is Brilliant
Great for flight sims, driving sims, and I recently acquired Arma3.....which is still gonna take some work for me to figure out
If you are thinking about TIR..... don't hesitate