Hi Rogueskywalker,
The first place I would start your research is the tutorial post here which has all the basic information, steps, and guidelines that can help you make the best possible choices … and know how to avoid the worst ones (including major brands such as Serta and the chain stores that focus on them). An exchange policy has little value if there aren’t any good quality or value mattresses to exchange for. There have been many members that have come here because they were “stuck” in between a rock and a hard place with a mattress purchased from a chain store such as Mattress Firm that wasn’t a good match for them and they didn’t have any good quality/value options to exchange for.
You can read my comments about Bedinabox in post #2 here. As you can also see in post #13 here … mattress reviews (or mattress review sites) are among the worst ways to buy a mattress since the large majority of the reviews are written right after a purchase, a mattress that works well for one person may be completely unsuitable for another person to sleep on, and most reviewers have little to no knowledge of the construction or the quality of the materials in the mattress they just purchased.
Outside of how well a mattress matches your specific needs and preferences in terms of PPP (Posture and alignment, Pressure relief, and Personal preferences) … the most important part of the value of a mattress purchase is the quality of the construction and materials in the mattress you purchase.
Brooklyn Bedding is one of the members of the site which means that I believe they compete well with the best in the industry in terms of quality, value, and service and they are completely transparent about the materials in their mattress. Once you are clear about the type of mattresses and materials that you tend to prefer (and it seems you may be leaning towards memory foam although I don’t know if you’ve tried other materials) they would be well worth talking with about which of their mattresses may be the best choice for you.
Some of the better options and possibilities I’m aware of in the Houston area are listed in post #2 here.
Phoenix