To cover, or not to cover. That is the question? At least it is when we haul things in the back of our F150! When it comes to hauling smaller items, or whenever it is raining, it is nice to have our access tonneau cover firmly in place. It helps keep what we're hauling dry when it is raining or inside the bed of our truck rather than being blown by the wind. It's easy to remove whenever we need to haul larger items, as well.
My husband loves that our tonneau cover helps cut down on gas mileage, even when we aren't hauling anything. Since the wind doesn't enter into our truck bed, there is less resistance (which is turn means great gas mileage).
Our tonneau cover has been well worth the money spent on it. Ours is a mid-range model, but we've heard that many of our friends with either low-profile or deluxe models are just as happy with their purchase as we are.