Unfortunately there isn’t a formula that can “calculate” the value of a mattress topper because there are too many unknowns, variables, and personal preferences involved … even if you are comparing similar toppers that are the same thickness and the same density.
The most important part of the “value” of a topper is how well you will sleep on it in combination with your mattress and the only way to know this would be based on your own personal experience. There are many different formulations of memory foam that can be very different from each other that can affect how it feels and performs relative to other similar toppers (see post #9 here and post #8 here).
The next most important part of the “value” of a topper is durability and in general terms higher density memory foam will last longer than lower density versions of the same material. I don’t know the density of the toppers you are comparing.
There is more information about choosing a topper in post #2 here and the topper guidelines it links to which along with a conversation with a reliable and knowledgeable supplier (that can provide you with good information about how their toppers and would be the most reliable source of information about how their toppers compare to each other or to other toppers they are familiar with that are available on the market) can help you use your sleeping experience as a reference point and guideline to help you choose the type, thickness, and firmness for a topper that has the least possible risk and the best chance for success.
When you can’t test a mattress/topper combination in person then the return/exchange policy of the retailer or manufacturer you are buying from (and any costs involved) can also be one of the most important parts of the “value” of a topper purchase just in case the topper doesn’t turn out as well as you hoped for.
I certainly agree with you about Dreamfoam and they sell great quality/value products. As you know they are a member of this site which means that I think very highly of them and that I believe they compete well with the best in the industry in terms of their quality, value, service, knowledge, and transparency.
Hopefully some of the members here that have purchased from Foamorder will see your post and share their comments but in the meantime a forum search on foamorder (you can just click the link) will bring up more comments and feedback about them as well. Even though they aren’t a member of the site (at least yet) … I also think highly of Foamorder as well and I would certainly consider them to be a reliable supplier.
Assuming that you decide to pull the trigger … I’m looking forward to your comments and feedback once you’ve ordered and received it and have had the chance to try it out.
Note Added Later: To elapid95
I got your message…No problem! I will proceed with deleting your old posts as per your request.
No problem! I will proceed with deleting your old posts as per your request.