On NCL it is usually six or seven times. That includes, Blue Lagoon (Ocean Blue) or whatever it's now called and O'Sheehan's. These are usually lunch or late night. It's nice to be able to get something more than pizza or a hot dog at 1:00 a.m..
Moderno is my favorite, followed by Cagney's. I did enjoy the noodle bar on Epic. The Italian restaurants have been my least favorite alternatives and, like Paul, I've found that Le Bistro isn't what it used to be but it's still pretty good.
I have had many good dinners in the main dining room and few "not so good".
I also love sailing on NCL in a full suite and enjoying breakfast and lunch in Cagney's. It is a nice perk and the food is a la minute.