I know not all people would enjoy VSync if they have a bad computer, but I for one would really like if I was able to toggle this on for myself – Even at 60 fps, the mouse feels really choppy because there isn’t any VSync.
VSync doesn’t fix input issues, it makes them worse. VSync is about screen tearing - it caps the refresh rate to that of your monitor. That means that you input is only getting handled at 60 fps as opposed to when it occurs.
What you’re looking for is just better mouse performance. The roblox mouse acts extremely strangely at low framerates, so this “choppy” behavior you’re talking about might be related.
EDIT: VSync actually wouldn’t do anything on roblox since it’s already capped at 60 FPS.