Jay Honeck wrote:

What I don't undertand it how you can turn your head left, let's say,
without losing sight of the screen, which is still in front of you?
They must somehow make the screen movements disproportionately larger,
to prevent this problem, right? But then I would think that it would
be very disconcerting, moving a little yet moving a LOT? Or do you
get used to it?

You can adjust the ratio of actual movement vs. screen view movement,
whereas 10º head movement might translate to a 45º movement on screen. They
have quite an elaborate calibration program for the individual users. I
tried one, but sent it back for a full refund after a few days - didn't care
for the feeling my head was stuck in traction to prevent any unwanted
wiggles on screen, plus if I reached for something like coffee, ah yeah,
coffee (or some other libation , things really went beserk.. Not to
mention I felt like a retard sitting in front of the computer with a hat on,
armed with reflectors.. d:-))