We chose our 2 week river cruise from Budapest to Amsterdam with Travelmarvel mainly from an economic point of view. My husband and I were travelling with my sister, and the single supplement for her on APT and Scenic was outrageous, and the single cabins were on the bottom deck at waterline. With Travelmarvel, my sister paid NO single supplement (she was not therefore eligible for free airfare, but still a lot cheaper) and her cabin was next door to our suite on the top deck.
We were a little bit anxious that the river ship might not be as nicely appointed as Scenic or APT, but we need not have worried. The ship was lovely, our cabin as spacious as a river ship can be, and the staff and food was excellent. Complimentary wine, beer and soft drink is available at lunch and dinner, and bubbles are available for free at the breakfast buffet too if you feel like it. The staff are very generous with the wine at meal times, with no waiting for a refill.
The only problem on the cruise was that we had to change boats halfway through as a Viking river boat had smashed into one of the canal locks and boats were unable to get through. This of course was in no way Travelmarvels fault, and they made the change from the Travelmarvel Diamond to the Travelmarvel Jewel as painless as possible.