Hi pressurepts,
While I can’t speak to how any mattress will feel for someone else or whether it will be a good “match” in terms of comfort, firmness, or PPP … all three of these mattresses are using good quality materials and there would be no lower quality materials or weak links in any of them relative to your weight range.
When you can’t test a mattress in person then the most reliable source of guidance is always a more detailed phone conversation with a knowledgeable and experienced retailer or manufacturer that has your best interests at heart 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 firmness levels to different body types, sleeping positions, and preferences (or to other mattresses that they are familiar with) than anyone else.
Because your own personal experience is the only way to know for certain whether any mattress will be a good “match” for you in terms of PPP … the options you have available after a purchase to “fine tune” the mattress or to exchange or return the mattress (and any costs involved) can also be a more important part of the “value” of an online purchase just in case (and in spite of the “best judgement” of everyone involved) the choice you make doesn’t turn out as well as you hoped for.
There are many versions of high performance polyfoam made by many foam manufacturers. While most of them are high quality materials … some of them can be closer to the properties of memory foam (lower resilience) and some are closer to latex (higher resilience) but in general latex will be more resilient than any of them so they would have less “bounce” than latex.
Having said that … the properties of all the layers and components in a mattress will have an effect on all the other layers and components and the feel and performance of a mattress “as a whole” so one mattress that contains a highly resilient material but also includes other less resilient materials (or where the higher resilience materials are thinner or deeper in the mattress) may have less “bounce” than a mattress that only includes more highly resilient materials (or where the higher resilience materials are thicker or closer to the top of the mattress).
Again … I would keep your expectations realistic and always keep in mind that when you are making an online purchase that the only way to know for certain whether a mattress you purchase that you can’t test in person first will be a suitable choice in terms of “comfort”, firmness, and PPP will be based on your own actual experience once you sleep on it.
If the only issue with a mattress is that it is too firm and there are no soft spots or sagging in the mattress and it is still in relatively new condition then a good quality topper can certainly be an effective way to add some additional softness, “comfort” and pressure relief to your sleeping system but the only way to know whether a specific mattress/topper combination is a good “match” for you in terms of PPP is based on your own careful testing or personal experience on the combination. If you can’t test the combination in person then there will always be always some risk and uncertainty involved in adding a topper because the specifics of the mattress itself along with your own body type, sleeping position, and preferences can affect which specific topper would be a suitable choice on any specific mattress.
If there are soft spots or sagging in your mattress then a topper generally wouldn’t be a suitable choice because the topper will just tend to “bend into” the soft spots or sagging areas in the mattress and the benefits of a topper may be limited or temporary.
There is more information about choosing a topper in post #2 here and the topper guidelines it links to which along with a conversation with a reliable and knowledgeable supplier (that can provide you with good information about how their toppers compare to each other or to other toppers they are familiar with that are available on the market) can help you use your sleeping experience as a reference point and guideline to help you choose the type, thickness, and firmness for a topper that has the least possible risk and the best chance for success. A good exchange/return policy can also reduce the risk of an online topper purchase so I would make sure you are comfortable with the options you have available after a purchase just in case the topper you choose doesn’t turn out as well as you hoped for.
If a mattress/topper combination turns out to be a good “match” for you in terms of "comfort and PPP then it also has the advantage of being able to replace just the topper without replacing the entire mattress if it softens or breaks down before the upper foam layers in the mattress (which is very likely because the upper layers of a sleeping system tend to soften or break down before the deeper layers) or if your needs or preferences change over time and a topper can also help extend the useful life of the mattress underneath it as well.
Phoenix