Hi edgerlys,
I don’t know the specific firmness of their Dunlop topper and they would be more familiar with it than I am so I would ask them for their thoughts about this based on their extensive experience with their own materials and mattresses. I can tell you that Dunlop latex is more supportive than other materials (it gets firmer faster as you compress it more than other types of latex) so it would be “less risky” to use for children in slightly softer versions than other types of latex or other foam materials. The most common suggestions for infants are “a firm surface” and for toddlers is “on the firmer side” but I don’t think that there is any definitive answer or specific consensus that includes every specific or every factor that is involved in “healthy sleep” for children.
I would personally be OK with medium/soft Dunlop if that’s what they are used to (assuming its in the range of mid 20’s ILD or so) because it’s already firmer and more “supportive” than most other “soft” materials but beyond this it’s really a matter of “best judgement”.
In terms of the quality or design of the mattress itself … it would depend on the specifics of the mattresses you are comparing, on the types of latex they used in each and your preferences, and on the design and all the components of the mattress including the cover and quilting. Both use high quality materials but they each have different options, designs, and benefits. You can read a little more about the different types of latex in post #6 here.
Other than the specifics of the mattress itself and assuming you are making “apples to apples” comparisons between them as closely as possible (similar designs and similar materials in each mattress you are comparing) … the choice between them would really depend on your personal value equation and all the parts of a mattress purchase (including all the other benefits, costs, or options that go with each one) that were most important to you.
They are both experienced, knowledgeable, and high quality manufacturers and would both make very good choices (I wouldn’t hesitate to buy from either of them) but once you have narrowed down your options to a final choice at each manufacturer you are considering (step 4 in the tutorial post) and are down to final choices between “good and good” then which one would make the best choice for you would depend on all the objective, subjective, and intangible factors that are most important to you. In some cases it may boil down to a very small detail or just which one you feel most comfortable dealing with if there is really no obvious winner between them or any “mistakes” based on your criteria.
Phoenix