Hi Diddlydo,
Weight (along with many other factors) has a direct bearing on how long any material will last before it softens or degrades or becomes unsuitable for your needs and preferences but this can be offset by choosing higher quality materials (in either latex, polyfoam, or memory foam) especially in the upper layers of the mattress along with choosing a firmer support core which will usually be necessary to prevent the heavier areas of the body (hips/pelvis) from sinking in too far and leading to support and alignment issues. If you buy a mattress with only “just enough” softness and thickness in the comfort layers to provide you with good pressure relief and perhaps a little firmer than you would prefer … then it will likely last you longer than a mattress that had a comfort layer that was already on the thick and soft side when you first bought it and will soon cross the line of being too soft when the materials soften further. Of course higher quality materials which keep their original properties for much longer are more costly but they have better value … particularly if the mattress is made by a better value manufacturer. The durability of a mattress depends on the individual because a mattress that may need to be replaced if it no longer provides you with comfort and support may continue to be both comfortable and supportive for someone else with different needs and preferences for much longer.
Body type along with sleeping position will also have a direct bearing on which mattress will match your needs and preferences or what I call PPP (Pressure relief, Posture and alignment, and Personal preferences). Different mattresses can be more or less suitable for different weights, body types, and sleeping positions. The “best” mattress for one person in terms of quality and design can be a disaster for another.
A topper is generally not a good idea on a mattress that has softened because it will just follow the dips and could lead to even worse issues of alignment because of too much soft foam on top of a support layer. A topper is much more suitable for softening up a mattress that is still in good condition but is too firm. It may provide some partial or temporary relief but in general you would be throwing good money after bad. The only way to really “fix” a mattress that has softened comfort layers is to remove them and replace them with better quality foam. It’s much easier to add softness to a mattress that is too firm than to “fix” a mattress where the deeper support layers are too soft or where the comfort layers have softened too much. There is more about this in post #4 here which has a few suggestions that may help but in general you are better off learning from the experience and choosing a more appropriate mattress that won’t have the same issues (or where the issues will take longer to develop) than the one you have (even though it’s better quality and value than most competing mattresses).
They are both a major manufacturer which I would avoid and an airbed which I think in most cases are a waste of money. There is more about airbeds and the reasons for my thoughts in this article.
Yes … I would say that probably 75% or more of the mattresses purchased today are much lower quality and value than they should be. The top 15 manufacturers control about 86% of the market and the top 5 control about 3/4 of this and most of the mattresses they make are not good value and in many cases use poor quality materials as well. there are several hundred local manufacturers that don’t advertise as much and aren’t as “flashy” but they have been making great quality and value mattresses for generations in many cases.
I would first spend a couple of hours reading the previous posts i mentioned and the other information it links to. This will give you a better understanding of what you may need and why the mattresses you have bought aren’t lasting you for very long.
If you did decide to buy a cheap air mattress then I would pump it up as firm as it will go and add a high quality topper of your choice of material (with a suitable thickness for good pressure relief). The same would hold true for a cheap innerspring but I would look for the best possible and firmest innerspring with the firmest, highest quality, and least amount of polyfoam above it and add a high quality topper to this as well. It may be difficult to find a good “base” innerspring mattress in this price range that doesn’t have too much cheap foam above the springs. Don’t forget that the much higher quality mattress you have from OMF only lasted for 2 years (although a big part of the reason for this was probably the suitability of the design) and a lower quality mattress will likely last even less. The goal with this type of “component” system is to have an inexpensive and very firm support base and then to spend the money for a high quality topper for a comfort layer to provide you with the pressure relief you need.
Hotel mattresses are usually no better than consumer mattresses (and often worse) but they are selected to be in a sweet spot that many people prefer “on average” and that will be fine for a few days, are usually in fairly good condition, and often use mattress pads or toppers that extend their life and can be replaced. There are countless people who for many reasons like a hotel mattress only to find if they buy one that they are not nearly as suitable in long term use at home and they are certainly not good value. I would put most of them in the “major brand” category which I would avoid.
Overall I would first see if any of the suggestions in the “mattress sagging” post may help and beyond this I would look at connecting with some of the better mattress manufacturers or sleep shops in your area to see what may be available either for a low cost “base” mattress that is suitable for use with a topper or for a better value and more suitable mattress that may be in your budget range. While I understand the attraction of low cost “fixes” … the quality of your sleep is also important and can have a bigger effect on how you feel than almost anything else you may buy and poor quality sleep for two years with a mattress that didn’t “work” for you would not be a “bargain” in my opinion … especially when if you know where to look and what to look for you can find great value in lower budget ranges as well.
Phoenix