Hi Argus McJohnsten,
The first place I would start your research is the mattress shopping tutorial here 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.
There is more about the most important parts of the “value” of a mattress purchase in post #13 here that can help you make more meaningful comparisons between mattresses but I would avoid all the major brands along with any mattress where you aren’t able to find out the quality and durability of the materials inside it (see the guidelines here).
You can see my comments about airbeds in this article. While any mattress may be a good choice for some people … in general terms I would look for other options.
[quote]Any recommendations?
Firmer the better
Quality and durability are more important than price, as long it's not too high
We are not small, I'm 6'4" 300lb and not graceful
I sweat a lot, so breathability should be factored in too[/quote]
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 for anyone to be able to predict or make a specific suggestion or recommendation about which mattress would be the best “match” for you in terms of PPP (Posture and alignment, Pressure relief, and Personal preferences) based on specs (either yours or a mattress) or “theory at a distance” that can possibly be more accurate than your own personal testing or sleeping experience (see mattress firmness/comfort levels in post #2 here).
Outside of the information in the mattress shopping tutorial (which is the first place I would begin your research) … there is also more information and guidelines for those that are in higher weight ranges in post #3 here and the posts it links to that will be helpful. The process of choosing a mattress for higher weight ranges would be exactly the same as for anyone else except those that are in higher weight ranges will generally need firmer mattresses and more durable materials than those that are in lighter weight ranges.
There is more about the many variables that can affect sleeping temperature in post #2 here that can help you choose the combination of materials and components and the types of mattresses that will have the best chance of keeping you in a temperature range that you are comfortable with.
Your best chance of success will be to follow all the steps in the tutorial one at a time. When you get to step 3 then the better options or possibilities I’m aware of that are in a reasonable driving distance (subject to the quality/value guidelines I linked) are listed in post #2 here for the area within about a 100 mile radius around Toledo.
Phoenix