Hi Wrester,
You can see the specs of the Reverie mattresses in the post I linked in my reply to you here.
Neither one (natural or synthetic latex or a blend) would have any harmful VOC’s but both of them would have some initial smell.
You can read more about the most likely reasons for temperature regulation issues in post #2 here but from the sounds of it the issue that a.stauff was having was connected to his blankets and sheets (he was too warm with one set of bedding and too cold with another).
Phoenix