I follow your point and it is possible but not that common - i lived in Thailand for a while and had them on my truck and had no problems.... but in some regions it may be a problem... middle east ?
yes heat is not top of your concerns.... i lived in Wales before Thailand ! we sell them on our website www.powerfuluk.com/vehicles/range-rover-evoque-sport/sport-2005-09/exterior-accessories/range-rover-sport-wind-rain-deflector-kit-4-pcs.html
The video might have been a little clearer if the fitting had been made to a light coloured vehicle instead of a vehicle much the same colour as the deflectors. Otherwise a clear and helpful video.