I think it is OK for my LV one. It is linked to a delrin shaft, and is not in contact with the (toasty hot) casework, and is a wood with a very high internal oil content (which is why it was used for ship's propellor bearings). I might get a bit more concerned with a really hard wood like ebony or african blackwood.
Anyone think about a one made out of natural stone, like marble, limestone or slate? Or one of the polymer composites like Corian.