We had a 3 day "bus cruise" to start as the ship could not get to Budapest due to water levels. The cruise director and concierge were very good though at organising and keeping everyone abreast of the changes. Unfortunately, once we did board, the top deck was only open for 1 evening before being closed for most of the cruise due to bridge heights. We were not aware of this and may have chosen a different cruise if we were aware of the issues with water levels and bridge heights.
Viking would not honour a $100 room credit we were supposed to receive, either for us or another couple travelling with us, even though they were given the paperwork showing we were to receive the credit.
Overall the service and food were good.
The cabin was fine, if a little cramped. We were on deck two. Be aware, if you spend more for a cabin on the top deck, you can hear the walkers going by over your deckhead.The shower was extremely cramped. I am pretty slim. Anyone who has mobility issues may have trouble with the shower. The service was good and was comparable to most other cruise lines