Frankly I can't think of a single flaw in the Hong Kong airport express system. It is magnificent. It is inexpensive, fast, clean, reliable, one always gets a seat and only makes two stops between the airport and Hong Kong island.

Further, there are check in counters at the express stations, making the outbound trip even easier. Finally, the taxi system at the stations is a wonder to behold: the station accommodates a plentiful number of taxis, loading from two sides in diagonal lanes. There never is a wait for a taxi and never congestion for cabs leaving. The best organized system that I have ever seen.

In short is it is everything that RER B is not.