When smooth turning is enabled, even when the speed slider is set to the maximum it takes around 12 seconds to turn 360 degrees. This makes the feature almost completely useless as it's so ridiculously slow. (Extremely slow rotations like this are also far more likely to induce nausea than short fast rotations).
Please adjust the slider so that the maximum turn speed is at least 10 times faster so players can choose whatever speed they like rather than being limited to the current range between "agonizingly slow" and "glacially slow".