This was one of the first podcasts I donated to and I felt lucky to have found it. I couldn't imagine how he did all the work needed to put the episodes together, even with a team. The storytelling is riveting, the fund of knowledge is huge, and the ability to connect events in unusual but thoughtful ways is unique. I don't think there are any new long form episodes or series, but the ones that are available are top shelf quality and worth the time and also worth the money. With so much free content out there, I wouldn't say that about any other podcast that I know of, unless you wanted total access to Marc Maron's WTF archives.
If you have any interest in history, this is the show to get. Some may complain that they don't release shows quickly enough, but with the amount of research that goes into them (and their sheer length), it's amazing that they put out as many as they do. Dan does a great job as a host/narrator and shows an astounding breadth of knowledge. He also brings you into the topic by relating it to modern times or giving you an existential question to ponder. Another good part of it is that they choose a wide range of topics, rather than focusing solely on one area or time period. Want to discuss the Cuban Missile Crisis? It's there. Genghis Khan? Yep. The rise of the Greeks? Sure, why not? I'm hoping one day for a series on New Zealand history/British colonization, and while I won't hold my breath, I know it's possible because of the many topics covered. Go get this show now!