I loved PC dining on the Star Princess. It looks like the Sapphire is different. They have four themed restaurants. IE: Santa Fe, Pacific Moon, Sterling, etc. So If I want steak and go to Sterling, do they also offer the regular ship's menu for my wife? Is Santa Fe only Santa Fe style cooking? Is Pacific Moon only Asian?
On the Sapphire ( I was on it recently), as stated above, you can order from any of the 4 PC menus and Traditional dining menu at any of the PC restaurants. And, you can do the same if you have traditional dining. So the menus are inter-changeable among all the restaurants except sabatini's. Some people shy away from traditional dining because they want to be able to have a variety of menus. Not necessary for reason stated above. Of course, if you want freedom to chose the time, then PC is for you.