The Mammoth HealthPRO Precision Mattress is an all-foam mattress with a lot of health language on the label, and I'd buy one of Mammoth's sprung HealthPRO models before it. It suits back sleepers and couples who want a still, even foam feel and don't run hot. "Medical Grade" is Mammoth's own trademarked name for its foam, not a medical standard, so judge it as foam.
Zoned foam over two support foams, and no springs
The comfort layer is 60mm of Mammoth's Medical Grade foam in three zones, with PostureCells cut into it so small blocks of foam move separately under you. Below that are an AdaptPro support foam and a firmer reflex foam, under a deep quilted top whose WAVE fabric has carbon particles infused into it. It's 28cm deep and no-turn, and Bensons sells it in Medium and Firm.
Expect an even, quiet surface. Cut-cell foam spreads your weight, and with no springs there's no bounce to carry a partner's movement across the bed. The trade-off is heat and lift: all-foam beds run warmer than sprung ones, the channels between the cells help without changing that, and foam gives you less push-back when you turn over.
Mammoth has a partnership with the Chartered Society of Physiotherapy, and says the society has given it design and testing expertise for over a decade. A tie with a professional body is worth more than most badges on a mattress, but it's a partnership with the brand, and it doesn't turn a foam mattress into a treatment.
Who it suits and who should skip it
Back sleepers of average weight who like a settled feel should take the Firm, and couples woken by a restless partner will like how still the surface stays. Side sleepers who choose Medium get a zoned top that lets the shoulder in a little. This is a new model with no owner reviews yet, so the verdict rests on the build.
Avoid it if you sleep hot; I'd put a sweaty sleeper on springs every time. Skip it if you change position a lot, because foam that cradles you also hangs on to you. And skip it if you assumed HealthPRO meant pocket springs, because the Precision has none, unlike the sprung models that share its name.
What to buy instead
Mammoth's sprung HealthPRO models, the Elite, Ultra and Advance, put dual-layer pocket springs under the same 60mm zoned foam, and that's the build I'd buy: the same cushioning with better airflow and more lift. If you like the idea of zoned foam but sleep warm, a latex-topped pocket-sprung mattress gives you pressure relief without the heat.
