We chose this cruise due to its unique Itinerary. We've had enough of St. Petersburg, which dominates the other Scandinavian cruises. We had never been to Iceland, the Faroe Islands or the Shetland Islands, or most of the other stops in Norway, Denmark or Sweden. My wife has never seen Norway. We loved Explorer during our Panama Canal New Year's cruise at the beginning of the year. It sails superbly, even in rough weather.
Explorer is one of our three favorite cruise ships, the others being Oceania Riviera and Marina (whence came Explorer's wonderful teaching kitchen, pan-Asian restaurant, and spa layout). Voyager and Mariner would come next on our list. The infinity pool is underutilized; people seem not to realize it's open to everyone. We went through the Panama Canal from there; far better view than from the Observation Lounge one criticism is the infrared "sauna," which isn't close to being hot enough for sauna lovers. Also, running out of aqavit on a Scandinavian cruise is inexcusable!
Food and service were excellent. We favor Pacific Rim and Prime 7, but Chartreuse was very popular too, though there is a strong split opinion; we much prefer Jacques on Oceania). Compass Rose is far better than the MDR on Oceania, but try to get a table in the quieter back rooms. One secret is the superb authentic Irish Coffee made in the Cafe.
For us, the Superior Suite is our "Suite Spot." As RSSC Gold members, we get several of the Concierge amenities and the larger verandah is wasted on this chilly Itinerary. My wife needs a bath tub and I like to take a bath too occasionally. Large walk-in closet is great. We have no interest in he higher categories.