It is my understanding that neither of these two products would be waterproof, but that is not a concern for me. I think that the St. Dormeir would be more water resistant than the Matelasse. And the Matelasse would interfere less with the feel of the Latex.
My priority in choosing between these two products is temperature regulation. Which of these two products would be better for keeping a cool sleeping surface?
Based on your comments you’ve probably read post #89 here about the different types of mattress protectors but strictly in terms of temperature regulation then wool would be more effective than cotton although there are also other factors that can affect temperature regulation as well that are discussed in post #2 here.
Post #22 here has more of a comparison between wool and cotton in terms of regulating temperature but in general cotton is more effective at “wicking” moisture away and wool (and other hair type fiber) is more effective at “storing moisture” and staying dry because it stores the moisture inside the fiber and keeps moisture and the heat it contains away from the body and allows the body to release more which is one of the keys to temperature regulation. The Dormier has both cotton on the outside for moisture wicking and wool on the inside for moisture storage. It’s similar to the temperature outside when the same temperature can feel warmer when the humidity is higher because the warmer and more humid air against the skin reduces the body’s ability to release more perspiration into the air around it because the air is already more saturated with moisture and acting as more of an insulator.
A forum member, Clawdia, just purchased the Cozy Pure and I think she plans on reviewing it when it arrives. Also, mike7 from that thread had got the st. Dormeir and they discussed it. There were some other mattress protectors discussed also.