Let's just say that Crystal offers a different product. If you like being called by name all day and night long (I don't) and having your family mentioned by employees....then go for Crystal.
I prefer the European style of service where my waiter is not my best friend for the duration of the journey. I have no interest in chatting with staff or having my room stewardess say 'oh that dress is so lovely. So nice you are wearing it AGAIN this cruise.'