This is the one most people try right before they find something better - a Tempur, a Simba, an Emma. Memory foam is a genuine step up from down or a flat block of orthopaedic foam: it moulds to your head and neck instead of fighting them, and it's the option most likely to be sold on a proper neck-support claim. But dense foam traps heat, so you wake up flipping it over to find a cooler patch that doesn't stay cool for long, and it compresses and breaks down within a year or two, quietly losing the exact support that sold you on it in the first place - and sold you on the £80–£150 price tag. You paid for the fix. A year later, you've got the same problem back, plus a hot pillow.
