The Bremen Passenger Lists were destroyed, during the war, I assume. A group reconstructed the Bremen lists from the arrivals in New York. Unlike the Hamburg Passenger Lists which sometimes have different information than the New York Passenger Lists, nothing is different in the published lists.
One example, my ggrandmother's entry on the Hamburg list, in 1850s, had her place of birth, which led me to her records and her family. With a common name, Hirsch, I had her parents names from her death certificate as well, so I took a chance on that town which had records available. They were indeed her parents in the town where she was born. Nothing like that would happen with the reconstructed Bremen Lists.