Our focus was on minimizing the plastic in the hot-water-path of the system (stainless steel boiler and stainless/steel spigot).   We are wary of the effects of passing hot-water through plastic, with the potential for leaching.  So, the water is heated in a steel boiler and dispensed through stainless steel (SS304) tubing.  This is also why we have focused on making our EcoPour filter All Paper.  As with any system, there are design/cost tradeoffs.  In our case, the reservoir is made of a FDA & NSF - approved, food grade plastic. It does not contain Bisphenol  derivatives (BPA, etc.) and Phthalate-based plasticizer components.