This is very similar to what we got with our Adventure Camper.
We were very impressed over the weekend - some awesome 4WDing and it handled it really well - it also funnelled out the dust away from the back of the car on the gravel roads - making it easier to see out the windows.
However, it does get quite dirty so you need to be careful on those dusty roads not to lean on it when getting things out of the car / fridge box. Helps to add a river crossing on the trip to clean it

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To access the back of the car easily, just a quick turn to the left or right and the stretchy bit leaves enough room to step through (if this makes sense?)
J