I have no idea about all your prayers,but I have
AIRTABS on my Class C.
They really help on a cross wind situation,no more sudden buffeting. It has stopped the sideways push when being passed or passing a large truck.
They are a vortex generator that produce a counter rotating air trail several feet behind the vehicle, This airflow alteration improves vehicle stability. As far a mileage it did not seem to make any difference