I am so glad a tour like this exists for the Grand Central Terminal. It was very informative and you will learn so many interesting trivia and tidbits you won't find anywhere else. The tour will take you to places inside the terminal that you will never know about and go yourself. The tour guide (Louis) was funny, entertaining, and always making sure everyone is doing okay on the tour.
I also appreciate that they gave each person a bluetooh earpiece so you can hear the guide loud and clear. I highly recommend everyone who love Grand Central Terminal to do this tour!