When we were on the Jewel there was a couple sitting next to us in the main dining room with one fellow eating the Kosher foods while his partner eat regular American prepeared food. It was quite the site to see this. The fellow was very particular and each entree was wrapped separately, and served in a plastic dish, similiar to a frozen dinner, that was plastic wrapped. He would not touch anything on the table and honestly we thought we had some kind of disease. In fact he created quite a show, with all the tables around him grining and grimacing. He ate several different dishes, 10 or 11 served for one dinner. The maitre de' was in attendence to carefully open each serving as he would only use plastic forks, knives, spoons. I am not sure if this procedure was usual for someone eating the Kosher prepared foods. From my observation he enjoyed what he ate, but carefully inspected every dish brought to him. I am not sure if this helps, but I found the whole ordeal to be rather disgusting and not appropriate for the main dining room. I think would it would have been better if he choose room service especially for the other diners. The whole ordeal was quite the spectacle. So I can't say that I ate the kosher food, but I am not sure if I could really enjoy eating dinner on a cruise ship like this.
I know I eat kosher foods at home, like kosher hot dogs and such, but I am don't worry about eating the hotdog on a bun or using regular utensils.