VSync is basically a function which will lock your maximum fps to the monitors refresh rate. It’s nothing to do with blender. You enable/disable it on your graphics card settings.
Turning it off can give higher fps, but if the monitor can’t refresh that fast there isn’t really any point. On slower systems turning it off can give a performance boost, but it introduces some visual problems.
Here’s an article on it.
I just tested this scene with VSync off and I get ~210 fps for both versions of the game engine. So there really isn’t much difference in performance, even though the profile would have you believe that :-?