Hi C10CoryM,
The first place I would start your research is the mattress shopping tutorial here which has all the basic information, steps, and guidelines that you will need to make the best possible choice … and know how and why to avoid the worst ones (including the Simmons mattress you linked).
I would avoid all the major brands and all the large chain stores (see the see the guidelines on this page).
There is also more about the most important parts of the “value” of a mattress purchase in post #13 here that can help you make more informed and much less risky choices and make more meaningful comparisons between mattresses.
If you let me know your city or postal code I’d also be happy to let you know about any of the better options or possibilities I’m aware of in your area.
Phoenix