Hi CherylB,
Welcome … and I’m glad you found us before you ended up purchasing a major brand mattress mattress from Sleepy’s.
The major brands such as Sealy/Stearns & Foster, Simmons, and Serta all tend to use lower quality materials in their mattresses than most of their smaller competitors that will tend to soften or break down prematurely relative to the price you pay which is why I would generally suggest avoiding all of them completely (and the major retailers that focus on them as well) regardless of how they may feel in a showroom along with any mattress where you aren’t able to find out the type and quality/durability of the materials inside it (see the guidelines here along with post #3 here and post #12 here and post #404 here).
I’m not sure what you’ve read since you found the site but just in case you haven’t read it yet … the first place to 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.
Two of the most important links in the tutorial that I would especially make sure you’ve read are post #2 here which has more about the different ways to choose a suitable mattress (either locally or online) that is the best “match” for you in terms of “comfort”, firmness, and PPP (Posture and alignment, Pressure relief, and Personal preferences) that can help you assess and minimize the risks of making a choice that doesn’t turn out as well as you hoped for and post #13 here which has more about the most important parts of the “value” of a mattress purchase which can help you make more meaningful quality/value comparisons between mattresses in terms of suitability (how well he will sleep), durability (how long he will sleep well), and the overall value of a mattress compared to your other finalists based on all the parts of your personal value equation that are most important to you.
The most common cause of lower back pain is a mattress that is too soft and I would tend to avoid a pillowtop or any soft mattress and look for something firmer. He needs a mattress that is firm enough to prevent the heavier parts of his body from sagging to much into the mattress and putting his lumbar spine out of alignment … and causing back pain.
Assuming that the materials in a mattress you are considering are durable enough for his body type and meet the quality/durability guidelines here relative to his weight range … the choice between different types and combinations of materials and components or different types of mattresses are more of a preference and a budget choice than a “better/worse” choice (see this article).
Each category can include hundreds of different mattresses with 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 will be a good “match” for him in terms of “comfort”, firmness, and PPP and others that use the same type of materials and components and are in the same category may 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 that would be just as durable. In other words different types of materials are a preference choice and he may like some types of materials or mattresses better than others but the design and firmness of the mattress (regardless of the type of materials) is the most important part of making sure his spine is in good alignment when he sleeps on the mattress.
Once you reach step 3 in the tutorial and you are ready to go and test mattresses with him then subject to confirming that any retailer or manufacturer on the list that you wish to visit is completely transparent (see this article) and to making sure that any mattress you are considering meets the quality/value guidelines I linked earlier in this reply … the better options or possibilities I’m aware of that are closest to Fauquier Co. would be in the list for the Washington DC area in post #2 here and the list for Fredericksburg, VA in post #9 here.
While I can certainly help with “how” to choose … It’s not possible to make specific suggestions or recommendations for either a mattress, manufacturers/retailers, or combinations of materials or components because the first “rule” of mattress shopping is to always remember that you (or in this case your son) are the only one that can feel what you feel on a mattress and there are too many unknowns, variables, and personal preferences involved that are unique to each person to use a formula or for anyone to be able to predict or make a specific suggestion or recommendation about which mattress or combination of materials and components or which type of mattress would be the best “match” for him in terms of “comfort”, firmness, or PPP (Posture and alignment, Pressure relief, and your own Personal preferences) or how a mattress will “feel” for him or compare to another mattress based on specs (either his or a mattress), sleeping positions, health conditions, or “theory at a distance” that can possibly be more reliable than his own careful testing (hopefully using the testing guidelines in step 4 of the tutorial) or his own personal sleeping experience (see mattress firmness/comfort levels in post #2 here).
You can see my thoughts about the type and quality of the materials in the Helix mattress along with many of the other simplified choice mattresses in post #2 here in the simplified choice topic and post #1 in the same topic would be worth reading as well.
Phoenix