Well I would have had some first-hand experience later this year as I was scheduled to fly through London-Gatwick to Windhoek. However, TIA, Air Namibia has just suspended their service from LGW. As of now, they are only operating out of Frankfurt although they have added an additional flight per week in order to compensate for the two London flights. (FWIW, Air Namibia is making a committed effort to accommodate passengers who had already booked airfare. We shall see how this ends up.)