Hi conceptcar3,
Just in case you haven’t read it yet … I would make sure you’ve read the tutorial post here which has all the basic information, steps, and guidelines that can help you with “how” to make the best possible choices … and know how and why to avoid the worst ones.
Post #13 here also has more about the most important parts of the “value” of a mattress purchase.
As you can see …the most important factor in the value of a mattress purchase is how well a mattress will match your specific needs and preferences in terms of PPP (Posture and alignment, Pressure relief, and Personal preferences) and how well you are likely to sleep on it. The most reliable way to predict this is your own careful and objective testing (using the testing guidelines in the tutorial post). If you are looking at an online purchase and you can’t test a mattress before you buy it then a more detailed conversation with a knowledgeable and experienced retailer or manufacturer that is more interested in selling you the “right” mattress out of the options they have available than they are selling you “any mattress they can” will be one of the most important parts of a successful purchase.
After the suitability of a mattress then the next most important part of the “value” of a purchase is knowing the quality and durability of the materials so you can identify any weak links in the mattress and make meaningful comparisons with other mattresses. The quality of the materials is the most important factor in the useful life of a mattress and how long you will sleep well on it. Post #4 here includes the foam quality guidelines I would suggest using to assess the quality and durability of a mattress and whether it has any weak links in the design.
Finally the other parts of your personal value equation that are important to you will also be a big part of the value of a mattress purchase and deciding on which of your finalists is the best choice for you. This would include the price of course and also the return and/or exchange options you have after a purchase and any costs involved which can offset the risk of an online purchase if you aren’t confident that a mattress will be a good match for you so you are comfortable with the options you have if a mattress you purchase doesn’t work out as well as you hoped and you don’t sleep well on it.
The tutorial post also links to a list of some of the better online memory foam options I’m aware of and if you are looking at a lower budget memory foam mattress then post #4 here also includes some of the better lower budget memory foam options I’m aware of.
The Foamex 12-Inch Ultra-Luxe Memory Foam Mattress uses 4 lb memory foam which is a suitable quality/density for those that aren’t in a higher weight range but they don’t list the density of the base layer of polyfoam which I would want to know. If your conversation with them gives you good confidence in their knowledge and experience and that this mattress would be a good match for you and assuming that the base layer meets the guidelines for a lower budget mattress then it would be well worth considering.
They are in the online memory foam list and would be well worth talking with to about whether this mattress would be suitable for you in terms of PPP. If they are familiar with the Optimum Radiance then they may be able to give you some idea of how they may compare but they use good quality materials in their mattresses and there are no weak links in the materials.
Dreamfoam is also on the list and they are also a member of this site which means that I think highly of them and that they compete well with the best in the industry in terms of their quality, value, and service. They would also be well worth talking to on the phone about whether this mattress would likely be a suitable choice for you in terms of PPP. They also have a 10" gel memory foam mattress here which uses 3" of 4 lb gel memory foam over a 7" 1.5 lb polyfoam base layer.
As you will read in the tutorial post I would tend to avoid the major brands as much as possible and I certainly wouldn’t spend any more on them than I had to. As you can see here … the Sealy Optimum Radiance Gold uses almost the same or lower quality/density materials as most of the other mattresses you are considering (about 4 lb memory foam and 1.5 lb polyfoam base layers) but is considerably more costly so I certainly wouldn’t spend any more “good money after bad” than I had to on any major brand mattress or on an “upgrade” unless there were no other suitable options available when the other mattresses you are considering use the same or better quality materials .
Phoenix