Are you sure the person you are buying for drinks their sake warm? There are excellent sakes that are served ice cold.
Because I drink mine cold, bamboo sets work well and have a nice feel to the hand. But they have two draw backs. (1) they absorb the flavor and serving anything other than sake is a bad idea once they have been used the first time. (2) they cannot be heated. Though the cups don't need to be, the serving piece would be better if ceramic.
Sake Masu, Bamboo & Wooden Sake Sets
Amazon.com: 5 pc bamboo sake set: Kitchen & Dining