We have cruised many rivers in Europe and also in Australia. We had taught in southeast Asian cities but never really explored the 'real southeast Asia, and the Mekong is such a famous river.
We chose The Jahan because it was quite a small ship (26 cabins) and the reviews we could find were pretty good , However, all the reviews understated the excellent hospitality, housekeeping, personal and marine staff. They were all so involved with making the cruise excellent and they genuinely cared. We visited great traditional sights and quiet little out of the way places and learned a huge amount of the culture and history of Cambodia (Days 1-5 and Vietnam (5-8).
Most days there was a an excursion in the morning, a fabulous lunch and a short siesta back on board and then another afternoon excursion further down river.