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No no and no. Get a Vispring. It really is the only option. They're utterly wonderful.
https://vispring.com/en-uk/
I was using these in the vernacular sense F as in "these 'ere foam jobbies" as opposed to the indicitive article.
They are not that expensive. Go into an independent retailer and you'll get one at around half price. If memory serves me correctly, I paid £1,600 for a super king size one with different firmness on each side.
For something you spend a significant portion of your life laying in, get a proper one.
Memory foam is for weirdos.