Hi bikegirl,
All the latex you are likely to encounter whether it is Dunlop or Talalay and made with synthetic or natural rubber or a blend of both has been tested either by Oeko-Tex or Eco-Institut for harmful substances using the same testing methods so they would all be “safe” by any reasonable standards. Other than this the only way to know whether any individual layers had more or less VOC’s and the specific amount of VOC’s in that particular layer compared to any others would be by comparing the results of a lab test. There are a lot of people on the internet that try to tell people that one is “safer” than the other but they have no evidence to show anyone and this is mostly about marketing.
There is more about the different types and blends of latex in post #6 here and more about the different certifications that you may see for latex in post #2 here…
Ammonia is mostly removed when the latex is foamed and all latex has a curing package that uses various chemicals to manufacture the latex. The only way to know the differences between different types of latex outside of the actual certifications would be to test the specific layer you are considering which of course wouldn’t be practical. Again … I would consider all latex to be a “safe” material other than for those that may have latex allergies (see post #2 here).
If what you are ordering is the same type and blend of latex manufactured by the same company then the product would be the same yes (outside of the smaller variations in firmness levels … seehere).
Post #2 here and the topper guidelines it links to can help you use your own experience on your mattress as a guideline to help you choose the thickness and firmness of a topper that has the best chance of success and includes a link to a list of the better sources for latex layers that I’m aware of as well.
Yes … I can confirm that Savvy Rest uses Radium for their Talalay and CoCo latex for their Dunlop.
Phoenix