@ Hi bcodemz.
Welcome to our Mattress Forum! 
As your questions are quite similar to drderek’s post above we’ve moved your post into this topic.
I understand your urgency to purchase a new mattress and you certainly aren’t alone … but this is exactly the time to slow down and do some preliminary research to learn about your broader needs and preferences, a few basics about mattresses, and to gather all the information you’d need to make a successful mattress choice. The first place to start your research is the mattress shopping tutorial here (there is a condensed version of it at the end of that post) which includes all the basic information, steps, and guidelines that can help you make the best possible choice … and perhaps more importantly know how and why to avoid the worst ones.
Your criterion is very broad and can’t be used in isolation … each mattress category can include hundreds of different mattresses with a very wide range of different designs, different “feels”, different characteristics, and different firmness levels. Every individual layer and component in a mattress (including the cover and any quilting material) will affect the feel and response of every other layer and component both above and below it and the mattress “as a whole” so each mattress category will generally include some mattresses that have a design that will be a good “match” for you in terms of “comfort”, firmness, and PPP (Posture and alignment, Pressure relief, and your own Personal preferences) and others that use the same type of materials and components and are in the same category and may be just as durable but have a different design or firmness level that may be completely unsuitable for you to sleep on … even if it uses the same general type of materials and components. Along with the support/firmness you’d also need to assess the comfort/pressure relief both of which are the most important functions of a mattress for everyone and the only way to know for certain whether any specific mattress will be a suitable choice that provides you with both will be based on your own careful testing or your own personal experience because different people can have very different needs and preferences in a mattress in terms of comfort, firmness, and PPP (Posture and alignment, Pressure relief, and your own Personal preferences) You can read more about this in mattress firmness/comfort levels in post #2 here.
Phoenix