Hi Franco,
Both the Nature’s Embrace Unison and the Snugsleep Latex Gold mattresses use only latex in the mattress so neither one has any lower quality materials or weak links in the design.
I would make sure that you confirm all the specifics of the Ironman Natural 1.0 to make sure that the materials that they listed are the only materials in their mattress as well (see this article). The law tag will also show if there is any other material besides latex in their mattress.
I’m guessing you’ve probably seen this but just in case the better options or possibilities I’m aware of in the Vancouver area are listed in post #2 here.
Post #13 here also has more information about the most important parts of the “value” of a mattress purchase that can help you make more meaningful quality/value comparisons between mattresses.
Phoenix