the roof vent on our van is starting to show its age, going yellow so probably brittle as well, motor slowing down, needs a reseal, so its time to replace. does anyone have an opinion on white /clear plastic versus the grey/black vents now on the market? some pretty fancy ones out there with reversable fans ,led lights and one that can vent even when closed, but what looks good on google has been known to be rubbish when they arrive , but really curious about the longevity of the dark plastic lids,