Oddly enough, I know a Rebecca who is also a Prima Diva.
First off, the numbers don't do you any good. That is so, the hardest way to go about things...so much so, that I don't use them for anything.
If you were to ask me what mattress compared to a number, I'd have to send off an email to someone who would do the same and wait for an answer that may or may not be accurate.
Forget the numbers. It's only making your experience worse. Compare specifications. It's the only effective way to shop apples to apples.
Next, I would suggest to you, that which I have suggested to many...using a 2" soft latex topper on whatever you buy to attain extraordinary comfort that lasts.
Now, if you are going to follow that advice, I would suggest that you get the topper first. Unzip your mattress. Remove the memory foam and replace it with the latex.
If you do this, you may very well find that you don't need to buy a mattress today. You could, very well, be able to put that off for a few more years.
Since you can't afford to spend much on a mattress right now, this course of action is dictated by sheer logic.
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