My wife & I were fortunate enough to have enjoyed (for $75) a TA ship's tour, including coach travel & lunch, on the Solstice whilst it was in port in Sydney just prior to Christmas in 2017. That sold us & shortly after, we booked the 2018 Christmas/NY New Zealand 12 night cruise. We'd not been to NZ previously & certainly hadn't sailed during the festive season. It would also be first time with Celebrity.
Initially it was just the 2 of us, but a few months' later a friend signed up & we changed our standard balcony cabin to a concierge class balcony room for 3.
As it eventuated, 2 more friends from USA wanted to do the trip & they booked a sky class suite. So all up, 5 of us, but in fairness, this review is based on my wife's & my experiences.
3 of us, all adults, shared this cabin. I was pleasantly surprised that the storage spaces took care of most of our clothing & effects, although a couple more drawers would've been helpful. All of our luggage fitted perfectly under the bed.
The cabin was as expected for it's class. Clean, reasonably spacious & so well maintained by our cabin steward Joaquim.