The ship was very comfortable, and the cuisine was excellent. Most outstanding was the service: the guides were excellent, and the cruise director was extremely helpful. I had a problem with my electronic reader that required a good internet connection, so she arranged to have a boat take me 10 minutes upriver to get a better signal. The only problem on the trip was poor internet connectivity, but I am told this will soon be corrected with a satellite internet system.
The sighting of creatures was somewhat disappointing; apparently there are few mammals or other large creatures close to the shore of the river because it can rise some 30 feet. The birds were very interesting.
I had some difficulty with walking on steep/rough/slippery terrain, and the guides helped me when needed.
Excellent: large, nice design, great bathroom, huge picture window to watch the shore go by; very comfortable.