Technically speaking, 60Hz/120Hz/240Hz will perform different temporal resolution (or someone call it fludility) if they all have same spatial/pixel level resolution at 1920x1080.
The best 仪器 in the world is our eyes, but there are plenty of calibration software available to professionally test quality in a standardize way. That aside,.60Hz to 120Hz is the most significant of these and the one showing the most dramatic reduction in motion blue and a smoother side to side panning which is noticeable under trained eyes.