"Authentic" Chinese dim sum "shines brightly" at these "well-run machines" in Annandale and Rockville, where "fantastic", "freshly made" noodles and "dishes you rarely see" are delivered with "no-nonsense bustle" in "'80s cafeteria" premises; yes, they're "short on charm", but "who cares" when the lack of ambiance translates into "rock-bottom prices" – just be sure to "bring cash" since they...