Hi Frances,
It’s very likely that he is right although some people are just more sensitive to smaller differences between two mattresses than others because they are closer to the “I can sleep on anything” than the “princess and the pea” side of the range so it’s possible that some people that are in a similar weight range to you may feel a difference that you wouldn’t notice.
While I can certainly help with “how” to choose … as you mentioned I don’t make specific suggestions or recommendations for either a mattress, manufacturers/retailers, or combinations of materials or components because the first “rule” of mattress shopping is to always remember that you are the only one that can feel what you feel on a mattress and there are too many unknowns, variables, and personal preferences involved that are unique to each person to use a formula or for anyone to be able to predict or make a specific suggestion or recommendation about which mattress or combination of materials and components or which type of mattress would be the best “match” for you in terms of “comfort” or PPP (Posture and alignment, Pressure relief, and your Personal preferences) or how a mattress will “feel” to you or compare to another mattress based on specs (either yours or a mattress), sleeping positions, health conditions, or “theory at a distance” that can possibly be more accurate than your own careful testing (hopefully using the testing guidelines in step 4 of the tutorial) or your own personal sleeping experience (see mattress firmness/comfort levels in post #2 here).
I’m assuming that you’ve read the mattress shopping tutorial (which is the first place to start your research) but two of the most important links in the tutorial that I would especially make sure you’ve read are post #2 here which has more about the different ways to choose a suitable mattress (either locally or online) that is the best “match” for you in terms of “comfort” and PPP (Posture and alignment, Pressure relief, and Personal preferences) that can help you assess and minimize the risks of making a choice that doesn’t turn out as well as you hoped for and post #13 here which has more about the most important parts of the “value” of a mattress purchase which can help you make more meaningful quality/value comparisons between mattresses in terms of suitability (how well you will sleep), durability (how long you will sleep well), and the overall value of a mattress compared to your other finalists based on all the parts of your personal value equation that are most important to you (including the price of course and the options you have available after a purchase if your choice doesn’t turn out as well as you hoped for … especially if you can’t test the mattress before a purchase).
While I can’t speak to how any mattress will “feel” for someone else because this is too subjective and relative to different body types, sleeping positions, and individual preferences, sensitivities, and circumstances … outside of PPP the most important part of the value of a mattress purchase is durability which is all about how long you will sleep well on a mattress. This is the part of your research that you can’t see or “feel” and assessing the quality/durability and useful life of a mattress depends on knowing the specifics of its construction and the type and quality of the materials inside it regardless of the name of the manufacturer on the label (or how a mattress feels in a showroom or when it is relatively new) so I would always make sure that you find out information listed here so you can compare the materials and components to the quality/durability guidelines here to make sure there are no lower quality materials or weak links in a mattress that would be a cause for concern relative to the durability and useful life of a mattress before making any purchase.
Since both of the mattresses that you mentioned are “all latex” mattresses then they would both be very durable choices and there would be no lower quality materials or weak links in either of them that would compromise their durability or useful life and I would treat them as being closely comparable in terms of durability (although of course they would probably be different in terms of how they feel).
The choice between Talalay and Dunlop is also a preference choice vs a “better/worse” choice and there is more about how they compare in very general terms in post #7 here but the only way to know which type of latex you tend to prefer will be based on your own local testing and/or your own personal experience.
When you can’t test a mattress in person then the most reliable source of guidance is always a more detailed conversation with a knowledgeable and experienced retailer or manufacturer that has your best interests at heart (which would certainly include Sleep on Latex) and who can help “talk you through” the specifics of their mattresses and the properties and “feel” of the materials they are using (fast or slow response, resilience, firmness etc) and the options they have available that may be the best “match” for you based on the information you provide them, any local testing you have done or mattresses you have slept on and liked or other mattresses you are considering that they are familiar with, and the “averages” of other customers that are similar to you. They will know more about “matching” their specific mattress designs and any firmness level options they have to different body types, sleeping positions, and preferences (or to other mattresses that they are familiar with) than anyone else.
As you probably know Sleep on Latex is one of the members of this site which means that I think highly of them and that I believe that they compete well with the best in the industry in terms of their quality, value, service, knowledge, and transparency.
I or some of the more knowledgeable members of the site can certainly help you to narrow down your options, help you focus on better quality/value choices that are available to you either locally or online, help you identify any lower quality materials or weak links in a mattress that you may be considering, act as a fact check, answer many of the specific questions you may have along the way that don’t involve what you will “feel” on a mattress, and help with “how” to choose but only you can decide which specific mattress, manufacturer, or combination of materials is “best for you” based on all the parts of your personal value equation that are most important to you.
Phoenix