Hi mimi42,
The first place to start is post #1 here and the information it links to. Reading through this (not “studying” it) will give you the basic information you need as a reference to help you make the best choices for you.
A mattress is only as good as the materials that are inside it. The brand of a mattress has little to nothing to do with it’s durability, quality, or value since any manufacturer can choose to use lower or higher quality/durability materials. They can also choose whether or not to disclose the quality of the materials that they use. The biggest “mistake” that consumers can make is to buy a mattress based on its brand instead of making their choices based on the quality and durability of the materials that are in it. It’s just as important now (for those who are looking for quality, value, and durability) to avoid the major brands like Serta or their iComfort than it was when the thread started.
The larger brands tend first of all to not disclose the quality of the materials they use which forces you to make a completely blind purchase. If you are able to do the research or have access to information that can find this out … you will find that at every price point they use materials that are lower quality than many of the smaller local or independent manufacturers. Lower quality means less durability, more softening and sags in the mattress. The loss of comfort and support because of softening or changes in the mattress materials is not covered by a warranty even though it is the main reason that a mattress needs to be replaced (as in your case). Warranties have exclusions which are designed to protect the manufacturer from having to pay most warranty claims.
This is why it’s always best to shop for a mattress based on the materials that are in it rather than based on brand. If you have a loyalty to the larger brands (and don’t know to exclude them from your options) … you will almost certainly end up buying less durable materials at a higher cost than many other choices you have available to you. You are also assured the frustration of not being able to find out the real quality of the materials in your mattress and have no way to make meaningful comparisons between mattresses. If you make a “blind purchase” in a mattress where you don’t know what is in your mattress (or don’t buy from someone who knows and has your best interests at heart) … the odds are overwhelming that (to use an analogy) you will end up buying particle board and paying real wood prices. You can’t feel quality in a showroom because low quality and high quality foams can feel exactly the same. The difference is that if you buy lower quality materials … what is happening to you now will happen once again with your next mattress … and possibly much sooner (quality levels have gone down since your last mattress purchase).
As you will read about in the link … it’s also important to know that the two main functions of a mattress are to provide pressure relief and spinal alignment in all your sleeping positions. The materials that you use to do this are a matter of preference. Memory foam, polyfoam, latex, innersprings, and all the other materials that are used in mattresses can all do this very well in the right combinations. No matter which material you prefer … the most important part is to use the highest quality of that material that your budget will allow. Memory foam for example in lower quality/density versions can soften and degrade faster than most other materials. The material you choose and prefer is not an “answer” as much as it is a preference and just one possible solution to the real goal which is what I call PPP (Pressure relief, Posture and alignment, and Personal preferences) and which uses high quality materials (no matter which material you prefer) that will last longer than lower quality versions of the same material.
So as you will read … the goal is to only deal with manufacturers or retailers that can tell you the quality of the material you are testing so that no matter how a mattress “feels” in a showroom that you have some assurance it will feel similar 6 months or a year down the road (and of course much longer).
Some of the better options and possibilities I’m aware of in your area (and region) are listed in post #2 here.
Again … the key to remember is to deal with “experts” that have the knowledge and experience to help you make the best and most suitable choices, so that you don’t have to become one yourself. Also … no matter what mattress you are considering or who you are dealing with it’s always important that you know the quality of the materials that are in it. If you aren’t dealing with someone who knows about mattress materials and can “translate them” for you … then you can always post the details they give you here for some feedback.
Phoenix