I recently flew from LP to Siem Reap on their ATR72 Turbo prop airplane. When my wife and I landed in Siem Reap. we were told that Vietnam Airlines had some issues regarding luggage and had without warning not loaded anybody's bags on the flight.
I'd like to say that the Vietnam Airlines representatives were helpful, but in reality there were NONE to be found. We were told by the airport reps to talk to people at the Vietnam Airlines office in town, but that "mysteriously" closed 15 minutes earlier than scheduled. Apparently this airline does this regularly and without warning for flights using this plane as it has a tight weight limit, but offer no compensation for the hassles and expenses you incur before the bags arrive a day or two later.
Bangkok airlines by the way was an absolute pleasure and I recommend them highly.