I used the automatic wash and paid for "ultimate". The under carriage blast did not remove the salt from the right side of the car at all and didn't "blast" the left. Rinse was poor leaving soap & salt residue on bumpers and the trunk. I saw no evidence (like water beading) of wax. The dryer is waste of time.
In short, take the time to drive down 22 to go to Sheetz.