Hopefully someone with firsthand experience will reply but to me...
The 790mm width is > enough Andy but the 1120mm length seems a bith tight to me. My XTR2 chair is 1160mm without me in it and the front of my feet protruding over the footrests adds to that. And the chair is longer if in tilt to any degree.
I see the Salsa Mini is 1100mm but add in your feet and any tilt and you'd probably exceed 1160mm?
Umm, no, not one of those, cool looking though it is
Head trackers are generally a lot less precise than eye trackers = much frustration and the trackers must be compatible with software which replicates a mouse, that one isn't. The Tobii has native Windows 10 eye control but also works with a few free open source programs.
Usually I'm about 60cm away but sometimes about 75cm and it works perfectly. Proper calibration is very important to ensure precision.
Love Ellie.