My father said that he and his pilot loved the Hercules motors as they were very reliable. Obviously the Beau was a heavy machine to haul around but the Hercules did not let them down. Later, whern they were given Mossies, the ones they had were old and many miles on them and the engines were not reliable. At the time, they wanted the Hercules on the Mossie! Eventually, they got some new Mossies with new engines and then they felt they had a great machine.
The picture could well be reversed, it just happens to be the only image of that machine in his collection.