Hi SMCK,
It may be a good idea to do some local testing (step 3 and 4 in the tutorial) so that you have a better frame of reference to “translate” much of what you are reading in more meaningful terms regardless of whether you end up making a local or an online purchase. If you let me know your city or zip code I’d be happy to let you know about the better options or possibilities I’m aware of in your area.
There are also several posts that will probably be among the most useful to focus on while you are doing the research that will lead to your finalists.
Post #3 here has more information that will be useful for those that are in higher weight ranges because durability will become a more important factor in your choice and in many cases a mattress that is suitable for someone in a lower weight range won’t be suitable for you.
Post #13 here has more about the most important parts of the “value” of a mattress purchase that can help you make more meaningful comparisons.
Post #2 here has more about the different ways to choose a mattress (online or local) and how to minimize the risk involved in each of them as much as possible.
Other than these it’s really a matter of following the steps in the tutorial post one step at a time until you narrow down your choices to a few finalists so you can make your “final choice” between them.
There is also more information about the many variables that can affect durability and the useful life of a mattress relative to each person in post #4 here and the posts it links to.
Post #2 here also has more information about the variables that can affect sleeping temperature so that you can choose designs and materials that are likely to be more temperature regulating.
The foundation post here has a few options for flexible bases that are both position and tension adjustable under the heading “Combinations of flexible, tension adjustable, and position adjustable bases:”
Hopefully this will help you to focus on the most important information that will help you narrow down your choices to a few finalists that are suitable for you in terms of PPP, that all use very high quality materials that are durable enough for you relative to your weight, and that are all good value based on all the parts of your personal value equation that are most important to you.
Phoenix