I've been on the Radiance (sister ship to the Brilliance) and the Star Princess. Star Princess wins in every category: If you mean the Norwegian star, I can't help you. Although I will be sailing her new itinerary in 2004
i.e. Cabins, comfort, service, food, management, etc. The Star Princess is just a fabulous ship in every way except exterior looks. The Radiance, a sister ship to the Brilliance, has very uncomfortable furniture throughout, is not as well run, and the food doesn't compare except in the Chops grill. I have not been on the Norwegian Star if that is the Star you have in mind.
As an example: We had a suite on the Radiance and they didn't have a beadspread to fit the bed if we wanted it in a double configuration. Thus our bed was turned down all day long. Not only that, these were cots, not beds and they were very hard to get any sleep upon, given the hard surface and squeaky frames and springs.That is not okay for your average "suites" customer. This is only two examples of many, as to why we didn't like the Radiance.
In my fourteen cruises the Star Princess was my favorite ship (except for embarkation) and the Radiance was my least favorite. The radiance didn't excel in any category (i.m.h.o.) except perhaps that she is very showy at first glance.