The guide made the tour and he was well informed. This is a fast paced and jammed packed tour. As long as you and your companions understand that you will be covering the sights quickly because so much to do, it is worth it. Since so much to see, not much idle time to see/take pictures of things not included on tour.
Since no one else had booked the tour, we had the tour guide all to ourselves and learned a lot of history. We covered Temppeliaukio (Rock Church) and Sibelius Monument up close; but saw Olympic stadium from a distance and saw (from a bit of a distance) National Museum of Finland, Parliament, and Mannerheim Statue. Saw up close Uspenskin Cathedral and Helsinki Cathedral, Senate Square, and Esplandi Park. We had lunch at Old Market Hall (on our own) and then saw the Sea Fortress Suomenlinna (rode ferry both ways). Also, saw up close various famous statues like Pavoo Nurmi. Loved to have had chance to wander or see the museum at Suomenlinna but just no time in the schedule.