I don’t see how you’d reliably get less than a frame of latency with vsync. If your mouse input lands while you are waiting for the next frame, you will lose at

I don’t see how you’d reliably get less than a frame of latency with vsync. If your mouse input lands while you are waiting for the next frame, you will lose at least one whole frame. In terms of comparison with an FPS, the same amount of responsiveness is required for any UI - ie. there should be no perceptual latency. Adding 17ms certainly is perceptual.