I think our guide told a good story, and kept the tour more personal than "tourish", which I liked.
As long as you keep the complimentary t-shirt as part of the package the tour has overall value. Our tour guide was very nice and knowledgeable about Key West "lore" but the places visited (with the exception of Capt. Tony's) were really of little (haunted story) value. Let's just say that we have been on each of the three "ghost" tours we know are available in Key West and the other two didn't need to provide t-shirts to justify the fare. Just not enough "meat" to the tour, but we had fun anyway.
We did the tour the first night we were in Key West. It was a great way to get oriented to the area and learn history about the town. It has more meaning to have history of the place you are visiting. Plus it is a fun way to get acquainted to the life style - ghost and all!