We've been to Tempura Kiku and really loved it. The food was good and the place was practically empty on a summer afternoon, so it was a nice break. But keep in mind the food is ALL tempura, as the name implies. (We did order a fresh fruit plate too, though.) So I think it really is a choice of food. We
haven't been to Coral Reef yet, but it is steak and seafood vs. the tempura food. Coral Reef also has the aquarium going for it. But Tempura Kiku has a nice view out into World Showcase.
Also, when are you eating? Will you be in future world or World Showcase?? Tempura Kiku is all the way on the far side of World Showcase.
Maggie