We took the Viking Cities of Light cruise from Paris to Prague. Initially, I must say that Viking's logistics were incredible. From picking us up at de Gaulle, to getting us to the airport in Prague, and everything in between, they were great.
Although we took the cruise for the beginning and end, the middle ports and cruising the Seine through all of the castles was just as good as the two ends.
In Paris, The hotel Pullman Eiffel Tower was ok, although the hotel concierge gave us incorrect information several times, and the elevators malfunctioned frequently. We picked up 4 day museum passes (at Les Invalides), rode the metro, and did as much as we could in 4 days averaging upper 90s in temperature. The best thing about the passes was skipping the lines at the Louvre and Versailles. The Opera House and LÓrangie were my highlights of Paris.
The cabin was very nice for a river cruise cabin. Well appointed, good shower, good service. We liked the number of plugs in the cabin, both European and American. We both had to work a bit while on board, and that made it easier to do. The internet connection was ok, not terrific, but it was what we expected, so it was just fine. The entire ship was a bit noisy.
The tour of the Bishop's residence was terrific. The guide was very good, and the building very worth seeing. Also enjoyed the brief walking tour of the town.
It was a great stop and thought provoking. I wish we had more time in Nuremberg. Guide was ok.