Please excuse my ignorance, but what can the Tornador Black do or do better that the Optimum Spray Gun could not? The Tornador Black is a bit more expensive so I am guessing it has more capabilities but I am not sure what they are.
You're comparing apples to oranges; the Optimum Spray Gun was intended to apply dressings to tires and trim, whereas the Tornador is intended to clean and dry multiple different vehicle surfaces and components. There are a lot of functional differences between the two.