We chose Amadeus Silver II by luck. We just saw a river cruise with a Grand Prix at the end of it and thought "why not?". It was our first river cruise but we've done dozens of sea cruises before. It turned out to be a great decision in fact!
The staff could not be more helpful, the food was outstanding, the ship was immaculate, our room (a suite with a small balcony) was just perfect.
Everything went like clockwork and everyone I spoke to onboard were impressed with the quality and service. We certainly plan to do another river cruise next year and we will be choosing Amadeus once again - this time by design rather than luck!