River cruising on the Rhine/Mosel provided us with the overview of first-time European visit. The stops were adequately timed, the river boat staff was helpful and the arrangements made for the shore excursions by Grand Central were very well done.
There were significant problems with the hearing devices allowing us to hear the guides that were not addressed until about half way through the scheduled dates. Complaints were not followed through until much too late and the groups were too large (much > than 25).
The major problem was with Grand Central's scheduling of our connecting flight on our return. They gave us MUCH TOO LITTLE time at the Paris Airport to make successful customs and connections. Then, our Air France hosts had no one available to help us make other arrangements until 2-3 hours later, after any remaining flights had left. After arguing with them for 3-4 hours, we finally received some vouchers for food and a local room. All this time, we were in contact with the Grand Circle "help" desk. They were of NO HELP WHATSOEVER. Their last comment after we had failed to find anyone at several Air France help desks was "go to the police"! That was the extent of their help.
Cabin was adequate, if small (expected). Bathroom and staterooms were maintained daily. View of river was good with a large window, except for the days when the riverboat was docked, often with the ramp cutting off our view. Noise levels were acceptable. Wi-fi mostly OK.