Shopping for a proper traditional mattress usually ends with the same wish list: pocket springs, natural fillings, tufts across the top and two sides you can sleep on. If that's yours, this is the bed I'd put at the top of it. Wentworth Mercer is Mattress Online's own brand, and the Deluxe Wool 3000 is the first rung of its ten-bed range with wool in it: one full layer of 3,000 pocket springs, wool under the cover on both faces, a Medium grade and 29cm of depth. It fills the gap between the cotton-and-polyester Natural Pocket beds lower down and the mini-spring Premium beds at the top. Lie down and the top inch is soft and dry, then the springs come up under your hip fast and keep you lying on the mattress rather than down in it.
Its neighbours make the choice simple. One rung down, the Wentworth Mercer Natural Pocket 2000 has 1,000 fewer springs, no wool and a Firm grade. One rung up, the Wentworth Mercer Deluxe Wool 4000 keeps the wool, adds 1,000 springs and goes Firm as well. That makes this the only Medium in the range with wool over a full layer of springs and no mini springs, and it's the Wentworth Mercer I'd point most people to. Two things to know before you order. The wool is one layer, with two layers of polyester fibre between it and the springs, so "Deluxe Wool" means wool on top, not wool all the way through. And it starts firmer than Medium: the owner who bought a super king calls it "firm not medium", so plan for a firm bed that eases a little over the first month and stays on the firm side.
Back sleepers of average weight are the easy fit, along with couples who like a springy bed they're happy to turn. Average-weight side sleepers will get on with it once the top has settled. Side sleepers under about nine stone should pass, because a Medium that starts firm will dig into a light shoulder for weeks. Skip it too if you're over about eighteen stone and want firm support, since the Firm 4000 is the rung for you.
For everybody else, buy it. You pay for the springs and the wool here, with no famous name on the label adding to the bill, and the springs and the wool are both the right kind.
Is the Deluxe Wool 3000 firm? Firmer than Medium at the start
Yes, at first. Mattress Online grades it Medium, a notch softer than its own Medium to Firm grade, and the owner who bought a super king found it far firmer than a medium should be. He put a topper on it, and after a month it started to ease a little. It's holding its shape, too. A topper was the right call: it fixes a bed that's too firm, and that's all it fixes, so never use one to hide a dip.
The build explains the firm start. A full layer of 3,000 springs pushes back hard, and the fibres above are packed tight and pinned down by the tufts. Fibre fillings soften and settle as you sleep on them, and Mattress Online's care guide treats some settling as normal in a bed with natural fillings. That is why the turning routine further down is worth sticking to: every turn gives the fibres on the other face a chance to recover.
Start with your weight, then your position. On your back or front at an average weight, this feels right from the first week. On your side at an average weight, you'll notice it at the shoulder for the first few weeks, then it eases a little, and it stays a firm bed. Light and on your side, add a wool topper from day one, or look at the softer Wentworth Mercer Deluxe Naturals 5000. Mattress Online will send an online bed to one of its showrooms for you to try, so if you live near one, lie on it on your side for ten minutes. You'll learn whether the firm start is too much for you, and that's the question that counts here.
3,000 springs in one full layer, with no mini springs
A full layer of around 3,000 pocket springs is a sensible count, and I wouldn't ask for more. Once a king passes about 1,500 springs, most of the extra on other mattresses is mini springs padding out the total, and I'd much sooner the money went on fillings. Its spring unit is one layer of full-height springs and nothing else. Further up the range, the Premium Wentworth Mercers stack their thousands of minis over just 1,000 full-height springs, which is why I rate this one as the better build.
The figure of 3,000 is the same on every size, so ask which size it's counted on before you compare it with another bed's total. The steel is tempered twice, which Mattress Online says helps the springs keep their bounce. What you'll feel lying on it comes from the count and the fillings.
Two rows of hand side-stitching run round the border to firm up the edge. The 4000 adds a rod wire round its edge, which makes it the stiffer edge of the two if you sleep right out to the side. Either way, don't treat the edge as a seat for long: Mattress Online's care guide for both beds says the same. It's made by hand in the UK, which is pleasant to know, and I still judge it on what's inside, which here is sound.
One layer of wool, then polyester fibres underneath
Under the soft viscose cover, each face has a layer of wool, then a thicker layer of soft white polyester fibre, then a thin polyester pad sitting on the springs. Your body meets the wool first, and the polyester does the cushioning beneath it. There's no cotton in it, and you'd have to go two rungs up to the softer Deluxe Naturals 5000 to get some.
Wool is the filling I'd pay extra for, because it sleeps cooler and lasts. Put it over springs with air moving between them and you've got the kind of bed I send hot sleepers to. The polyester fibre won't regulate warmth the way wool does, but it breathes far better than a slab of foam. One owner came to it from a mattress that left her too hot to sleep, and she calls this one "super comfy" without that problem.
That's the bit I care about. My duvet is a heavy one all year round, because the weight helps me settle, and a cool bedroom balances it out. A mattress that adds its own heat would undo all of that, and this one won't. The tufts that hold the fillings in place show as small dimples across the top. They stop the wool drifting into lumps, so I count them in the bed's favour.
A turnable bed with a busy first twelve weeks
It's double-sided, with handles on the side for turning it, and I'd always choose a bed I can turn. A mattress you can flip lasts longer, because the wear goes onto two faces. The routine is busy early on: a rotate or a flip every fortnight for the first twelve weeks, then both every two months for good. That's more than most people bother with, and it's the one bit of upkeep that pays off. Natural fillings need that rest to recover, so get a second person in for anything bigger than a single and keep to it.
Keep it clean as well as turned. The care guide says stains, or skipping the routine, can count against a guarantee claim. Clean it with a vacuum and an upholstery head, and keep liquids off it altogether. I'm not keen on protectors, since they cut how well a mattress breathes, but this one needs a breathable protector twice over. The 100-Night Comfort Trial depends on it too: you buy Mattress Online's own protector with the mattress, sleep on it for about a month, and if the firm start hasn't eased for you by then, they'll exchange it for another bed. It's a swap, with no refund.
At 29cm, about 11 and a half inches, it takes ordinary deep fitted sheets without a struggle. A single can come by standard delivery, and every bigger size comes with a two-person crew, so book a day you'll be home and pay for collection of your old mattress rather than leaving it for landfill. Its price flips between two levels every few weeks, so if it's at the higher one when you look, wait for the drop.
What to buy instead
Want it firm and still want wool? Buy the Wentworth Mercer Deluxe Wool 4000: the same idea with 1,000 more springs, a rod wire round the edge and a Firm grade, which suits heavier back and front sleepers. If you can live without wool, the Wentworth Mercer Natural Pocket 2000 gives you a Firm, turnable bed on 2,000 springs under cotton and polyester.
If the budget won't stretch, the Wentworth Mercer Natural Pocket 1500 costs less and is the best of the cotton beds, turnable and Medium to Firm, though you give up the wool and half the springs. And if you want wool and cotton together, look at the Millbrook Wool Luxury 4000 at the same shop. Part of its count is mini springs, so it doesn't beat this bed on springs, but Millbrook sits in that middle ground I like: a fair price for a high spec.
