Hi Wrewster,
Newton Rest hasn’t launched yet so there is little information available about either the mattress, the materials they are using, or how it feels and performs outside of the proprietary names they are using. As you probably know they plan to launch their crib mattress first and then their adult mattress (see here).
If I had to guess it is probably made from some type of densified PET fiber that would be similar to this and this but of course that’s just speculation based on the limited information that is available.
There is a little more about Sleep Studio / Authentic Comfort and Michael Rothbard in post #2 here.
Phoenix