Hi znosaro,
I switched your post into a new topic of its own with a more descriptive title because your questions about other mattresses were outside of the scope of the original topic you posted in.
I’m sorry to hear that your BME mattress was too firm for you but the good news is that you had the foresight to purchase a mattress with a great return policy so you could try it out without any risk.
If your mattress is too firm then some of the comments in post #2 here may also be helpful.
I would keep in mind that there are no “standard” definitions or consensus of opinions for firmness ratings and different manufacturers can rate their mattresses very differently than others so a mattress that one manufacturer rates as being a specific firmness could be rated very differently by another manufacturer. Different people can also have very different perceptions of firmness and softness compared to others as well and a mattress that feels firm for one person can feel like “medium” for someone else or even “soft” for someone else (or vice versa) depending on their body type, sleeping style, physiology, their frame of reference based on what they are used to, and their individual sensitivity and perceptions. There are also different types of firmness and softness that different people may be sensitive to that can affect how they “rate” a mattress as well (see post #15 here) so different people can also have very different opinions on how two mattresses compare in terms of firmness and some people may rate one mattress as being firmer than another and someone else may rate them the other way around. This is all relative and very subjective and is as much an art as a science.
In other words … the only way to know for certain whether another mattress would feel softer or firmer to you and “how much” it would feel softer or firmer (particularly if it’s rated in a similar firmness range) and whether it would be a good “match” for you in terms of comfort, firmness, and PPP (Posture and alignment, Pressure relief, and your own Personal preferences) will be based on 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 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.
While again nobody can speak to how any specific 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 and you are the only one that can feel what you feel on a mattress … outside of PPP and how well you will sleep on a mattress which is the most important part of “value”, the next 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 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 in your bedroom 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 your weight range in terms of the durability and useful life of a mattress before making any purchase.
You can also see some comments about the type and quality/durability of the materials in the Leesa and the Helix mattresses (and many of the other simplified choice mattresses as well) in post #2 here in the simplified choice mattress topic.
Phoenix