Hi digiorknow,
Leaving out the unknown of the polyfoam core density of the Serenity, all of the other layers seem to be good quality materials, and the Gaffney also uses high quality materials.
There is no “chemical free” mattress (even pure water is a chemical ), and all latex foam (including 100% natural Dunlop and Talalay and organic latex) uses a small amount of chemicals to manufacture the latex (see post #18 here) but the manufacturers don’t release the specifics of their compounding formula which is a closely guarded secret.
While I’m not a chemical engineer so I can’t speak to all the differences in their chemical formulations … the two main “chemical” differences between Talalay and Dunlop is that Talalay latex uses carbon dioxide gas as a gelling agent while Dunlop latex uses sodium fluorosilicate. Natural Dunlop latex is also often manufactured closer to the latex plantations so in many cases it needs less ammonia or other stabilizing agents to stabilize the latex and prevent it from coagulating or putrefying before it’s used while Talalay is made in Holland (Radium) or in the USA (Talalay Global) so the liquid field latex they use may contain higher levels of ammonia or other chemicals to stabilize it before it’s used to manufacture the latex. Most of the ammonia is removed during the foaming process either way.
The real issue that I would focus on is safety which depends on the specific chemicals and the amount of each chemical (safety is dosage related) and the only way to identify any safety issues would be based on the lab testing and certifications for the materials and components in the mattress or the mattress as whole.
The only reliable way to assess the “safety” of different materials in more general terms is based on lab tests and the certifications they have for harmful substances and VOCs so that you have some assurance than the VOCs are below the testing limits for the certification (see post #2 here for more information about some of the more reliable “safety” certifications). If the materials in a mattress or the mattress itself has a reliable “safety” certification then for most people they would certainly be “safe enough” … regardless of the type of material or the name of the manufacturer on the label.
Based upon the information on their web site, the WInndom seems to use Mountain Top Foam, 100% Natural, in the continuous pour Dunlop process. The would be a high quality material, but you’d still want a complete listing of all of the componentry within the mattress.
Leggett and Platt (and others) have been producing innerspring units with a steel spring edge system for a few years now. These tend to work better on adjustable bed base units, and depending upon the configuration, can hold up better along the edge than a polyfoam system, are easier to compress and ship, and also have a more “gradual” transition from the main part of the mattress to the edge. Like any innerspring unit, there are different variations, but in general the innerspring unit itself is usually not the wink link within a mattress.
If you’re interested in their mattresses, you may wish to phone them and see if they have a showroom on site or allow consumers to visit.
Off the top of my head, Bay Bed, My Green Mattress, and SleepEZ offer two-sided latex mattresses. A few others do custom orders and may be able to configure what you’re looking for, but you’d want to place a phone call with them.
Most latex mattress manufacturers will prefer that your mattress be place upon a firm un-flexing surface, as opposed to an active coil box spring. If you’re using a slatted platform bed, slats with reinforcement in the center with 3" or less between them would be recommended. Proper foundations for latex mattresses are discussed in more details here in the foundation thread.
Phoenix