While the rich flavor of Pusser's Rum is natural, most other major rum brands add flavoring agents and sugar to make their products smoother and to give them body. By contrast, Pusser's uses no flavoring agents or sugar. It is all natural.
Pusser's "Navy Rum" is not just a name for dark rum. Originally it was the name of a specific type of rum distilled for the Admiralty in wooden pot stills in lieu of the normal metal ones. Pussers begins its aging process with a rich flavor already in place from the distillation process, one that would not be possible without the wooden distillation. Thus when the aging process is completed, the full flavor of Pusser's surpasses by far that of any other rum because the wooden distillation provides an extraordinary head start over anything distilled in metal.