Stanwell - The TP was splendid for the sort of 'unprepared' strips which were standard in the area at that time but required a dedicated operating crew, whereas the Devon was a 'fly yourself' machine and standardised for most Air Attaches.
Re the aircraft mix at Vientiane, it was quite remarkable - Helio Couriers, Beech 18s, Lockheed Ventura,, C123s, C46, C47, Caribou, Otter et al. A 'spotters' paradise!