Hi Lulu0915,
There is more about organic Dunlop latex in post #6 here and more about organic certifications in general in post #2 here. I would keep in mind that outside of the certification itself there is very little to no difference in the latex itself compared to 100% natural Dunlop.
The choice between Dunlop and Talalay latex is a preference choice not a “better/worse” choice and I would choose the combination of layers that your testing indicates is the best “match” for you in terms of comfort and PPP (Posture and alignment, Pressure relief, and Personal preferences). You will always be the best judge about how soft or firm any mattress or layer feels for you regardless of how it may feel for anyone else. There is more about how Dunlop compares to Talalay in post #7 here.
All the latex you are likely to encounter (Dunlop or Talalay made with either natural or synthetic rubber or a blend of both) will all have been certified by either Oeko-Tex or Eco-Institut for harmful substances and VOC’s (see post #2 here) and I would consider any type of latex to be a “safe” material as well. There isn’t any “toxic” or “unsafe” latex.
There may also be some other options in the Chicago area that are worth considering as well and the better options or possibilities I’m aware of in the area (subject to the quality/value guidelines here) are listed in posts #2 and #4 here
The tutorial includes a link to a list of the members here that sell mattresses online (in the optional online step) that compete well with the best in the industry in terms of their quality, value, service, and transparency and many of them also make latex and latex hybrid mattresses that use different types and blends of latex that have a range of different designs, options, features, return and exchange policies, and prices that that would be well worth considering. Some of them are very similar to the Savvy Rest mattress but are in a much lower budget range and have a better exchange/return policy as well (Savvy Rest doesn’t allow returns).
Phoenix