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In this guide
The Koala mattress will suit side sleepers well (in fact, it’s our pick for the best mattress for side sleepers) because it provides great alignment for side sleepers’ necks and spines. As a side sleeper, Elese loves the supportive softness that’s good for pressure relief. It’s also good at minimising partner disturbance as the foam absorbs pressure well, making it ideal for co-sleepers.
Hot sleepers, people who have particularly wriggly co-sleepers or people who need extra back support will find a lot to enjoy in the Emma Diamond mattress. With prices starting from $2,499 this is definitely more a master bedroom mattress than a guest or kid’s one.
Ali reckons side and back sleepers who prefer a medium to firm mattress will love the Emma Diamond. Because it combines the hugging feel of foam with the support of springs, weight is distributed evenly making it a good choice for anyone with back pain.
We rate the Koala mattress better than good - we rate it great. This foam mattress is dreamily soft yet supportive and breathable. We love that it’s really effective at minimising partner disturbance. Koala itself has a top-notch approach to environmental sustainability which is a big tick for us. Oh, and it comes with a little Koala toy. What’s not to love?
- The soft and cosy feel.
- Less deep than other mattresses in a box, so fitted sheets fit easily.
- Customisable firmness level that can be flipped.
- Koala’s commitment to doing good for the planet, people and animals.
- No handles which makes turning and moving it pretty difficult.
- A little hot during Aussie nights, especially in comparison to the Eva mattress which Elese has also tested.
- The pressure relieving feel of the mattress that moulds to your body.
- Great suitability for hot sleepers.
- None to very little motion transfer.
- Very little off-gassing smell.
- Even though Emma says it’s medium-soft, most sleepers find it firm especially for the first few weeks. Our sleep tester Ali reckons it’s medium to firm.
- Lack of edge support makes the sleepable area of the mattress feel smaller.
- Rope in someone to help you manoeuvre the mattress as it’s quite heavy.
The Koala mattress is a foam mattress that boasts 3 layers:
- A 7cm comfort layer topped with a breathable Tencel Lyocell fabric that’s 35% Tencell Lyocell and 65% polyester.
- A customisable firmness layer that can be flipped. One side is medium-firm, the other side firm. You can change the firmness by unzipping the mattress and flipping this layer.
- The final support layer that has 3 different support zones to cradle every inch of your weary body and prevent your hips sinking too low.
All the foam is polyurethane foam that’s certified free of formaldehyde and other nasties and is low-VOC (volatile organic compounds).
Unlike the Emma Comfort, the Emma Diamond is a hybrid mattress. This means it’s got both foam and springs in 4 layers:
- Diamond Degree graphite foam which helps prevent heat build up and reduces partner disturbance.
- Adaptive comfort foam which is pressure relieving and responds as you move for all-night comfort.
- Pocket springs which increase air flow for a cool night’s sleep and minimise partner movements.
- HRX foam for extra support, especially for your back.
The Emma Diamond mattress has a removable and washable cover that’s 99% polyester and 1% elastane. The bottom of the cover is 100% polyester, while the base is 87% polyester and 13% polypropylene.
The Koala mattress comes with a 120-night free trial which is slightly longer than the average (100 nights). Shipping is free nationwide (apart from weekend delivery which costs $70) and can be same day in metro areas. Outside metro areas, you’re looking at 1-15 business days. They have a delivery checker on their website so you can get a more accurate idea of how long it could take. You might even get a cheerful delivery person who’ll help you tackle the stairs.
The Koala mattress has an industry standard warranty of 10 years.
You’ve got 100 nights to try the Diamond. If it’s not right for you within this time, you can send it back. Emma asks that you give it at least 3-4 weeks before returning it. Returning it involves emailing them to arrange a free pick-up. This only applies to customers within their delivery area. Customers outside these areas (which aren’t listed on their website) need to take the mattress to their nearest drop off location, at their own time and expense. Once Emma has the mattress, they refund you within 14 days.
The Emma Diamond mattress has a 10-year warranty. This warranty covers sags or dips that are greater than 2.5cm, cracks or hollows in the foam, a mattress that doesn't fully inflate within 2 weeks, and damage to the cover (but not normal wear and tear). Claiming under the warranty involves emailing Emma with photos of the problem.
Emma offers free shipping, Australia-wide. Delivery timeframes vary massively. For in stock Diamond mattresses, you’re looking at 1-7 business days. But for those on backorder, it can be between 6 to 9 weeks. Unfortunately this seems to be where Emma struggles. There are some unhappy Aussies complaining that shipping has either been massively delayed (way beyond 6-7 weeks and into 4-6 months) or simply hasn’t turned up. Communications with Emma have been reduced to automated emails telling customers their order is delayed. It’s a shame that these shipping issues seem to be detracting from a great mattress.