I was testing this myself earlier today. In my experience, if you max out the sensitivity settings to 100, there is definitely a noticeable difference and the controls are a lot more sensitive. The game controls are very sensitive to begin with. For example, the camera vertical/horizontal at 100 means the camera will rotate quicker than the player model can keep up, so you can see the players shoulders. When they're at 0, you can't see the players shoulders.