For me, it's about the texture in the rice rather than the taste. The microwave rice cookers that I have tried usually makes the rice very mushy. As long as you put in the right proportions of rice to water, a rice cooker makes it consistent everytime, anytime. It also keeps the rice warm and you don't have to worry about burning or maintaining the rice because you can pretty much just start it and forget about it. However, a lower-end rice cooker will not do this as well as a higher- end one. A higher-end rice cooker can hold the rice for a long period of time without a noticeable drop in quality or texture. To me, when I'm preparing a meal, the last thing I want to have to worry about is rice unless I'm making a risotto, paella, etc.
"Boldness has genius, power, and magic in it."
Johann Wolfgang Von Goethe