It would probably help with the temperature inside the vehicle, it's a well-documented fact, that the color white reflects the suns light & heat.
So, if that's your sole reason for doing it, it would probably be a worthwhile modification.
However, from an aesthetic point of view, I don't think it would be visually appealing, but that aspect of it, may not be very important to you.
Of course, that's just one man's opinion.