Sleeping Duck vs Koala
“There's nothing worse than a
sag-prone mattress.
That's why I put the Sleeping Duck Mach II
mattress up against a foam only mattress.”
Lawrence
Koala mattresses are made entirely from foam. It's important to know this because it directly affects how long your mattress will last. Foam only beds tend to soften and sag over time, offering less support for your spine.
Sleeping Duck's Mach II combines adaptive comfort foams with twice tempered steel springs giving you lasting strength, mobility, and support that foam alone can't match.
Steel springs matter. They prevent sagging, improve airflow, and keep your back well supported for the lifetime of the product.
“Founded by Aerospace Engineers, Sleeping Duck has been designing, engineering and manufacturing mattresses and beds for over 14 years.
Over that time, tens of thousands of customers have slept on the products for more than a decade and they couldn't be happier with the result.”
To Make Life Easier,
Here's a Direct Comparison
| Sleeping Duck Buy Now | Koala Luxe | |
|---|---|---|
Price (Queen) | $1,649 | $2,151 |
Product Review Rating | 4.8 / 5(Trusted by over 5,600+ reviews) | 4.8 / 5(Only 1490+ reviews) |
Award Winner |  Best Mattress Winner 2025 | None |
Adjustable firmness |  Fully modular (soft → extra-firm) can adjust firmness during trial |  Fixed |
Dual firmness (partner sides) | Each side individually adjustable | No partner customisation |
Construction | Hybrid: adaptive foam + twice-tempered steel springs | All-foam (no springs) |
Back support | Engineered spring system for long-term spinal alignment |  Foam can lose support over time |
Edge support | Reinforced steel perimeter resists sagging | Foam edge softens over time |
Washable cover | BreathTech cover is removable and machine-washable | Not removable |
Cooling & airflow | Excellent airflow with spring core + BreathTech bamboo cover | Standard copper-infused foam for basic cooling |
Integrated Sleep System | Works seamlessly with the SD Indestruct Bed (steel frame, lifetime durability, designed for optimal mattress performance). | No equivalent engineered base system. |
Trial period | 100 nights+ free firmness swaps | 120 nights |
Warranty | 10 years | 10 years |
Australian designed | Yes | Yes |
Best for | Couples, adjustable comfort, strong back support, hot sleepers, heavier sleepers, and anyone who values a mattress that evolves with their needs over time. | Sleepers who are happy with a single, one-size-fits-all foam mattress and don't require any customisation. |
 |
Sleeping Duck Guarantee
They Can Get It Right For You
“There is a huge difference between a flippable layer and sleeping duck's interchangeable firmness system”
FIRMNESS ADJUSTABILITY RANGE
Sleeping Duck Has 4 Distinct Firmness Options
This system gives you four distinct firmness options - Extra Soft, Medium, Firm, and Extra Firm, that you can mix and match across each side of the bed.
You can change them at any time during your 100 night trial, free of charge, with help from our team.
Because we care. We want to work with you. And we want to make sure you get the best sleep possible every night, for years to come.
Koala Has a Flippable Firmness Layer
There's a flippable foam layer meaning it's one single piece of foam you can flip to choose between firm and medium firm.
It's a relatively small change to surface feel, but the structure underneath stays the same. Once you've flipped it, that's it there's no deeper adjustability or individual side control.
“Don't Take My Word for It.
Ask Your Friends”
Sleeping Duck has won countless awards, and in a recent CHOICE consumer survey, Sleeping Duck scored the highest rating for customer satisfaction of any mattress brand in Australia. A whopping 90% satisfaction rating!
I encourage you to do your research. Ask your friends. Read real reviews. You'll quickly see why more Australians choose Sleeping Duck for lasting comfort and support.
Sounds great but I have a few questions?
Koala's 7-zone support core is designed to contour to your shoulders, hips and lower back, which can feel comfortable for side sleepers but because it's a fixed foam design, the firmness can't be changed after purchase.
Sleeping Duck gives you more flexibility. Our customisable firmness pads let you tailor your comfort level with four firmness options, medium, firm, extra soft, and extra firm. If you find your mattress too firm or too soft, you can adjust it any time during your 100-night trial, free of charge with help from our team.
Here's how it helps in real life:
We went with Sleeping Duck because it offered adjustability.
I'm a side sleeper and always end up on the same shoulder it's much better with the soft pad. My partner prefers a firmer side, and we can each have our own firmness. Sleeping Duck sent the softer pads at no extra cost, just as advertised.
Mark, 55-64, side sleeper
They make a big difference and it's not just marketing. Koala's Luxe mattress relies entirely on foam for support. It feels great at first, but foam alone can soften over time, especially under the heavier parts of your body like your hips and lower back. That's when sagging and reduced spinal support start to appear.
After about 4 years the mattress started sagging, and by 5 years the bed now gives us way more back pain than we initially had.
Verified Koala customer,
ProductReview.com.au
Sleeping Duck uses a foam and spring system featuring twice tempered steel springs the same process used in aerospace engineering to create lasting structure and strength.The springs respond individually to your body weight, keeping your spine properly aligned and preventing the mattress from dipping or flattening over time.
The result? Consistent back support, better airflow, and a mattress that feels like new years later, not one that gradually loses shape.
Fair question and it's actually why we started Sleeping Duck in the first place.
We saw how confusing the mattress industry had become, endless models, technical jargon, and claims that all sound the same. So instead of making ten different mattresses, we built one, and made it adjustable so every customer can get it just right from home.
Koala's cheaper models use all-foam designs. Foam feels soft and comfortable at first, but it naturally breaks down over time especially around the hips and lower back leading to sagging and reduced support. Sleeping Duck's Mach II uses a hybrid system of premium foams and twice-tempered steel springs, engineered for long term structure, airflow, and consistent back support.
And the results speak for themselves. In the 2023 CHOICE consumer survey, Sleeping Duck achieved a 90% customer satisfaction score, ranking ahead of Koala's 84%. So while Koala offers a range of foam mattresses, Sleeping Duck delivers one mattress built to last, designed to adapt, and proven to perform.
What Sleeping Duck Customers Say