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We reckon side sleepers will get a great night’s sleep on the Koala Calm As mattress. With its 5 layers and foam construction, it offers a lot of soft, sinkable support for side sleepers’ necks and spines, helping to keep them in the correct alignment. The Original Koala mattress (the precursor to the Koala mattress) impressed Cosier writer Elese with its minimal partner disturbance and the Calm As mattress, with 2 extra layers, will be even more effective. Co-sleepers, this one’s for you.
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 reckon so. Designed to suit a range of sleepers, but especially good for side sleepers, the Koala Calm As foam mattress is great at providing supportive comfort all night long. It suits Aussie sleepers well, thanks to the attention paid to keeping you cool as you sleep. Partner disturbance is also minimal. Koala itself is a great Aussie company with some really solid eco-credentials.
- The supportive comfortable feel of the mattress.
- Customisable firmness level that can be flipped.
- The attention paid to keeping you cool on hot nights.
- Koala’s environmental and sustainability focus.
- It’s pretty deep at 29cm so check if your fitted sheets will work.
- No handles which makes turning and moving it tricky.
- It’s heavy, weighing up to 51.75kg for the king - those handles really would have come in handy.
- 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 Calm As mattress is a foam mattress with 5 layers:
- A 7cm polyester sleeping surface and a 1cm quilted cover. This sleeping surface is designed to keep you cool and dry as you sleep.
- Flippable comfort layer which offers you a medium-firm or firm feel.
- A support layer with 3 support zones that are targeted to your important bits, like your back and shoulders. It’s got air tunnels too to help air move freely and avoid that sticky feeling. It’s also designed to spread your weight evenly across the mattress.
- Another support layer, much deeper this time. It’s the firmest core of the mattress and should provide great support for every type of sleeper.
- Edge support to make sure you don’t sink when you perch on the end to put your socks on.
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.
With the average free trial period being 100 nights, Koala beats it by offering 120 nights. Koala will only pick up the mattress for free in most areas of Sydney, Melbourne, Brisbane, Perth and Adelaide. If you’re outside these areas, you’ll need to bring it to the nearest Koala warehouse - ouch. Although they promise a full refund, note that delivery fees are non-refundable.
Koala ships for free nationwide, although they do offer weekend delivery for $70. Delivery 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.
The Koala Calm As mattress has an industry standard warranty of 10 years that covers any physical damage and defects in the materials and workmanship. It doesn’t cover normal wear and tear, which includes ‘softening of the product that does not affect performance’. This sounds a little subjective to us as your idea of your mattress becoming too soft they might argue isn’t performance related.
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.