We just returned from a wonderful cruise on the Explorer. Previous cruise was on Enchantment of the Seas. Explorer is a huge ship though not so big that you would get lost. The staff was ultra-friendly, the ship was clean and very well designed.
We had all of our dinners in the Columbus dining room and were very pleased with the service, the food quality and choices. We had breakfasts and lunches in the Windjammer except for one lunch at Johnny Rockets. The Windjammer food was varied and was fine. The desserts were especially good! As I said, we had lunch at Johnny Rockets and were pleased with the food quality. We left feeling overly stuffed and hardly any appetite for dinner. My husband really liked the jukebox at the table that takes nickels (provided by the waiter) so he could listen to oldies! There is now a cover charge of $3.95 per person plus a charge if you order milkshakes, beer or soda. We still thought it was pretty darn good. I don't think I could've eaten there more than once though.
We went to the fitness center a few times. They have a lot of great equipment, similar to the gym we belong to. It tends to be quiet in the evening but I noticed early mornings are crowded.