We started our cruise with 3 days in Prague, organized by Viking. They had a desk manned 12-13hrs a day at the wonderful hotel they booked us into. They were very helpful getting our British Airways lost luggage back to us. We had a newer, clean bus to take us from Prague to Budapest, where the river cruise started.
The Viking cruise from Budapest to Amsterdam was fantastic. The ships were almost brand new, the crew and the meals were wonderful. Through no fault of Viking we had to swap ships halfway along the route, as the water level was too low in a stretch of the Rhine/Main canal for the ship to navigate. A sister ship was coming the opposite way from Amsterdam, so they took a bus ride from their ship and we took a 3hr bus ride to their ship. Luggage was all handled and the new ship was exactly like the one we had just left.
The local guides at each port were fantastic and very knowledgeable of their area. Meals on and off the ship were excellent and tours were arranged to accommodate almost all levels of fitness. Embarkation and Disembarkation were as painless as these two activities can be.
The cabins aboard the Viking Alsvin and Ingvi were very well appointed and very comfortable. The cabin staff did an excellent job of looking after any needs.
Again though I must caution that the rooms on a river cruise are much smaller than on an ocean cruise. For example the only place to sit in our French Balcony room was on the bed. However there was adequate space for closets and dresser drawers. TV and free internet (sometimes spotty) were a nice bonus.