We sailed the ARosa Aqua along the Rhine from Basel to Amsterdam. It was our second river cruise and an unforgettable experience.
The ship was clean and nicely appointed. All cabins are the same size, I believe 165 sq. ft, but the design made the most of the space. Large bed - 2 twins put together, good walk-in closet space, functional bathroom with enclosed shower and a french balony. The crew were very courteous and eager to please.
The food was exquisite - right on a par with the best cruise lines. Especially enjoyable was the all-inclusive aspect, so no need to whip out a card every time you order a drink, etc. Not to mention a nice supply of Havana Club rum!
Other passesngers on ths cruise were mostly if not all American, generally in the 50-75 range and pretty experienced travelers from what we could tell. Everyone got along very harmoniously.
There were included shore excurions daily in every port, and even bicycle tours offered. The tours were very good for the most part. The ports themselves were well-chosen, our favorite being Strasbourg. Entertainment was not so remarkable, but also not expected on a ship like this.
In essence our experience was very, very positive and we would highly recommend it for someone who would like to experience an overview of slightly "off the beaten path" ports in an easy, relaxed and all-inclusive manner at very good value.