My husband and I took the tour in July of 2014. Dan was a passionate, funny, and incredibly well[-versed guide. We got to learn about so much of Salem's history, including a lot of the nautical history that is sometimes overshadowed. There was a great balance of humor, history, anecdotes, and lore. As others have said, you definitely get your full money's worth as the tour will last 1.5-2 hours. It is very well-paced, though, so you never walk too far at a time or stand in one place for too long.
I would definitely recommend the tour and would go on it again next time we are in the area.