Landing distance is a very big example of what you can demonstrate at an air show (or put in the brochure) being very different from what you'd actually want for sustained operations.
That said, it's really a factor of approach speed (where the Su has the wing and controls to be quite good), brake capacity and the ability of the controls to put weight on wheels. The 'phoon, incidentally, has fan-cooled brakes so it can turn around quickly after a short landing.