Just returned from 7 not Cruise on Quantum. Overall, we (me, husband and young adult son) really enjoyed the ship. It is large (not as large as Oasis but still felt large enough) which we like because that typically means lots of activities and a newer ship. Felt that held true for Quantum; while the activities were similar (bingo, trivia, dance parties, games/sports, fitness activities) every day there was plenty to do. Ship is in great condition and well maintained.
Bumper cars were really fun and unique to have on a ship. Other posters have mentioned to try and book your free Ifly and Northstar appts as soon as you get on the ship; this is true. They book fast. We did not get Ifly spots but did get Northstar. Unfortunately, we ended up having to miss it because we stayed later than expected in port on the day we were scheduled to go up. We weren’t too disappointed as it was very cloudy that day so I don’t think we would have seen much. Solarium area was our favorite spot. 270 was a nice area as well; wish we had spent more time there with the floor to ceiling windows.
Service was excellent for the entirety of the cruise; everyone we interacted with was friendly and eager to assist. Our room steward was the best we have ever had on a cruise—he made us some very cool towel animals.