I had the grand tour and I enjoyed seeing the rooms of the place and the grounds. Reserve tickets online in advance, entry times are staggered and limited, book a tour if you can. The crowds were manageable and not overwhelming. Great history, fantastic display of art and fabulous gardens. The audio guide was very good with interesting history about the Hapsburg family and how the Austrian royal family lived their lives. Empress Maria Theresa's rooms were especially enthralling.
Such an impressive building. You can walk around the park for hours, you can have a picnic, there is a Zoo, there is a labyrinth part which is really fun. A bottle of water and good shoes are helpful for the park. You can climb up to the Gloriette and look over the park and the city. The place is incredible, and a great walk through history.
Photos taken with Sony DSC-HX50B.