CybOrgasMatrix dolls used an elastic gel, which they claimed to be superior to silicone in elasticity, shape memory, and durability. Both this company and the company "First Androids" once offered pelvic thruster motor, audio capability and heated orifices, though these options are no longer available. Several modern doll manufacturers now offer the last option on their silicone dolls, with the addition of an internal heating system.
Now, TPE stands for thermoplastic elastomer, which is essentially a mixture of polyvinyl chloride and silicone. This is a type of skin that is very soft, and it mimics the feeling of human skin. TPE is way more realistic in feeling and it definitely mimics the feeling of human skin. It also is much cheaper than silicone alternatives, sometimes even hundreds of dollars cheaper. TPE also allows you to move the doll around in various ways, since it has more flexibility. TPE dolls don’t really need to be bathed, but you can, just be mindful of the water. It also is hypoallergenic as well.