We were invited to join friends on this cruise and are so glad we did. Our cabin was on the lower deck (230) and was very comfortable. It was above the water level and had a full picture window, unlike the standard cabins on the Rhine and Danube. No complaints at all. The food was excellent as was some of the local Russian wine. Our somewhat complex travel arrangements were expertly handled by the Viking travel desk. The only negative was that two of my flights in Europe were booked in basic economy class so I got hit with two unexpected baggage charges, but when I complained to Viking they refunded the amount of the charges.
You can see photos and some background on our cruise at
Surprisingly spacious, bed very comfortable, bathroom ergonomic, nice to have a full picture window. The cabin steward kept the room spotless. Every time we left for a meal or excursion we came back to find that the cabin had been tidied and cleaned. I liked the Russian toiletries less than the l'Occitane ones you get on the Rhine and Danube cruises, and we were more conscious of noise from the nextdoor cabin than on other Viking ships but those are the only things I can think to carp about!