We chose this cruise based solely on the itinerary, R/T San Diego and to go to Machu Picchu which had been a bucket list item for many years. Aside, from Lima, the ports were very unusual -- not in a good way. The west coast of Central and S. America was not a trade route so, towns were usually a couple of hours inland with not much to see. Once you've seen one Aztec or Mayan ruin, you've pretty much seen them all. I guess if you haven't ever seen really large ruins in other parts of the world they would be interesting. Our ports were, for the most part, cargo/container piers.
Our cabin had water problems for 3 of our 4 weeks. Issues were smelly water backing up in the tub and sink and a broken pipe under the floor between the bathroom and closets. There was no connection between the two issues. The staff was extremely nice and apologetic but, could not make up for an old ship. Unfortunately, the ship was sold out so we could not move to a different cabin. One Neptune cabin had no AC for the entire month long cruise. Imagine spending that kind of money and to suffer with heat?
Dining room menus didn't appeal to us and we only ate there once. We dined quite a few times in the Pinnacle and mostly in the Lido. Both were excellent.
The cabin was quite small and, as mentioned above, major water issues.