The main plastic seats provide more comfort because they are often ergonomically designed and are easier to clean than wooden toilet seats. Wooden seats are usually heavy, and "heavy" doesn't mean "better quality" because colors can fall off more easily (colors can't fall off on plastic seats) and liquid is absorbed more quickly, especially when the seat has got some cracks. Wood is a more natural material and can be painted easily and cheaply - especially in China, which is now done, so wooden seats are usually cheaper. In addition, plastic seats may be slightly colder than wooden seats in winter.