Hi LikeToHike,
I think I confused myself and you
My last reply was to both your post and garaet’s because I didn’t notice they were from two different people and even though it was mostly about your questions I addressed it to garaet instead of you and included my comments about the generic information he posted as well.
I changed it to be a reply to you and your questions and addressed the “non specific” comments I made about the information garaet posted to him. Sorry for any confusion.
If your box spring doesn’t have any obvious weaker or soft areas and provides a good even supportive surface then it would likely be OK at least for a while. My tendency though would be to replace it though since its 10 years old. The post I linked to earlier links to two other posts which have examples of some of the lower cost wire grid or slatted foundations that are available.
Getting a good nights sleep and waking up without pain (unless there are other reasons for the pain than a mattress) is all about choosing the layering that gives you the best PPP (Pressure relief, Posture and alignment, and Preferences). The overviews I linked to earlier gives some general guidelines about the different types of mattresses and construction that tend to be more suitable on average for different heights and weights and sleeping positions. Quality is always relative to your budget though and lower budget mattresses generally include less costly materials. The goal is always to find the best quality materials in your budget range. Denver Mattress has good value and have some good options and of course the members here, Including Brooklyn Beddings Ultimate Dreams, sell what I consider to be among the best quality and value mattresses available in the country.
If I was in your shoes though … I would either look at Denver mattress again where you can personally test a mattress for pressure relief and alignment (personal testing is usually more “accurate” than an online purchase) or if you are comfortable with an online purchase that has no returns or exchanges (but allows you to choose the firmness of the comfort layer to best suit your needs and preferences) … then the Ultimate Dreams uses much higher quality materials than the “norm” for its price and has very good value. The two latex mattresses at Denver mattress would be worthwhile testing though if for no other reason than getting a rough sense of what 24 ILD talalay latex feels like which you can use as a guideline.
If you would like more options … then post #21 here includes a list of the manufacturers that are members of the site who specialize in online purchases and are very good at helping people make good choices over the phone using a combination of their height/weight/body shape and sleeping positions and any local testing they have done as a guideline. Most of these are in a higher budget range though but most of them also offer either layer exchanges or returns which may be important to you. Which is “best” for you really depends on what is most important to you or what I call your own personal “value equation”.
You are at a place where all your options are good ones and there are really no “bad” choices. It’s just a matter of deciding which of them best fits your budget, the type of mattress you want, your risk tolerance, and how important local testing and exchange/return policies are for you.
I hope this helps but if you have more questions that I haven’t covered … feel free to post them
Phoenix