We had a 2 hour tour the day before with Gabriella so 5 hours tour was too much for the city. Value added was not great and we got to see most of the sites again but during daylight. Gabriella did a wonderful job at the Schönbrunn Palace and was very informative.
TOUR GUIDE RESPONSE: We did a completely different tour the second day: Schönbrunn Palace and the Hundertwasser House which we both didn't see the first day. We did a part of the Ring Street again by daytime - it looks very diffent with the illuminations by night and some buildings are not illuminated - so for me it makes sense to do it by day and by night. At Schönbrunn there were long queues and we got inside immediately without waiting time. The overview tour in the city is 3h, Schönbrunn 2h, 5h was perfect timing.