We loved sailing on Oasis and Allure, and assumed Harmony would be the same. Certainly it has a lot of positive features: water slides, the revamped decor.
However, there was ONE key negative that will lead us to avoid this for future cruises and go back to Oasis or Allure:
Customer service
Loved the decor so much more than Oasis or Allure. Great storage and space. Loved that the loungers on the balcony actually reclined, and wasn't that plastic-ribbon type material on the previous ships.