I went on the 6pm Segway tour that covers highlights along the Mall for about 2.5 hours. There were only five people in our group led by Alisse (very charming and knowledgeable). Segway training started promptly with a safety video and then hands-on practice. Bike and Roll clearly takes safety seriously because we were not going anywhere until we had all mastered the Segway and satisfied the leader. This is a good thing! That said, I swear to you... after five minutes on the Segway it will feel totally natural to you. If you have any doubts or fears at all, just let them go!
Now about the tour... we stopped several times for commentary from Alisse. Being on a Segway, we were able to cover a lot of territory - almost 10km - in 2.5 hours. Although this tour is too early to see the National Monuments at night, the sunset is very lovely too. We passed nearby the National Museum of African American History just as the sunset was illuminating it - it was like a shining jewel, so beautiful. There was an extended stop at the Lincoln Memorial with enough time to venture inside (if you can bear the crowds!) or the short walk to the Vietnam Veterans Memorial (also crowded).
One highlight for me was the long journey down the middle of Pennsylvanuia Avenue (in the uncrowded bike lanes) from the Capitol all the way to the White House. You could build up some good speed and see things from the same vantage as the President during the inaugural motorcade!
This tour covers a lot of territory very efficiently, but in my opinion it is not a substitute for a proper National Monuments or Capitol Hill tour (walking or cycling) if you really want to learn about them. It is a fun overview. I really enjoyed it!