We've done about 45 RCI cruises, and last year did our first on Celebrity, wow!, what a difference, reminded us how RCI used to be. We sail RCI more for the ship as we've been to most of the ports they service, we did the Celebrity as it went from Dubai to Singapore. I thought the Edge was in lovely, not all the bells and whistles of RCI but apart from the indoor skydiving on quantum class we don't tend to use slides etc. Service was so much better on Celebrity all over the ship from the cafe to stateroom attendant to restaurant service. We ate in the dining rooms in the evenings, did not try any speciality ones as the MDR seemed same standard as speciality on RCI.
We've since booked 3 more on X, still like RCI and have some booked with them.