Sleep seems simple in theory, but anyone who actually tries to get a good night’s rest knows it can be a delicate art. Choosing the right mattress to fit your body, your partner, and your ever-changing sleep habits can feel like trying to solve a Rubik’s Cube in the dark.
I’m a true combination sleeper – sometimes on my back, sometimes sprawled on my side, and occasionally doing what I can only describe as a full-on starfish pose – so I’ve spent countless nights tossing and turning. Most mattresses either lean too soft, letting me sink like a marshmallow, or too firm, leaving my joints crying for mercy.
Harrison Sprinks’s grassington 5750 pocket mattress promised to be the remedy. In the name of journalism, I slept on it for two months to see whether it really is perfect for combination sleepers. I wanted to be able to lie in various positions and still feel comfortable and supported.
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How I tested
I slept on the Harrison Spinks grassington 5750 pocket mattress for two months alongside my partner, giving me plenty of time to really get to know it. For context, I’m a combination sleeper, so I focused on how well it adapted to different positions – back, side, and front – and whether it kept my spine aligned throughout the night. I made sure to note down how I felt in the morning, including whether I woke up with any stiffness or aches.
I conducted a series of tests to analyse its motion isolation, including the water glass test, to see whether any spillage occurred when the mattress was jumped on. Lab-style tests are all well and good, but I wanted to see whether, in a real-life setting, I could feel my partner tossing and turning. Another important factor I considered was how well it could regulate my temperature. While I haven’t tested it during the summer months (I’ll update this review after the first heatwave of the year), I considered how the mattress felt on unseasonably warm evenings, as well as cooler nights. Here’s my full testing criteria in more detail:
- Comfort and feel: I took into consideration how the mattress supported my body when sleeping in different positions and whether it provided the right balance of cushioning and firmness.
- Spinal alignment: I am prone to lower back pain, so I paid attention to how my back and hips felt in the morning to see if it relieved aches.
- Motion transfer: I monitored whether my partner’s movements affected my sleep. I also placed a glass of water at the centre of the mattress and applied various amounts of pressure around it to see how well the design protected against movement.
- Temperature and breathability: The mattress was tested during winter but I assessed how it felt on warmer evenings compared to cooler nights.
- Consistency over time: I made note of any changes in support, firmness, or sagging to judge long-term durability.
Harrison Spinks grassington 5750 pocket mattress
Mattress sizes (UK): Single, double, king, super king, emperor
Mattress type: Pocket sprung
Guarantee: 5 years
Brand’s sleep trial: 60 nights
Rotate or flip: Rotate
Tested by: Front-, back- and side-sleepers
Firmness rating: Advertised as "Medium to Firm" | Rated by tester as 8/10
Depth: 28cm
Cover: Not removable
Old mattress recycling: £35 (via Mattress Online)
Why we love it
- Works well for people who change positions during the night
- Balanced medium-firm feel suits a range of sleepers
- Impressive motion isolation for fidgety sleepers or couples
Take note
- May feel too ‘bouncy’ for people who favour the enveloping memory-foam feel
Initial thoughts
The Harrison Spinks grassington 5750 mattress is substantial. It’s hefty – definitely a two-person job to manoeuvre or rotate – but that weight gives it a reassuringly premium feel. The layers feel soft to the touch yet solid, and the finish is understated but undeniably high-quality. Even before lying down, it looks durable.
Overview
After two months, the mattress has transformed my sleep. For me, the tension feels like a sweet spot that makes it ideal for restless sleepers who switch between positions through the night and it adapts quickly so I never felt stuck or restricted.
The pocket springs give it a responsive, sturdy feel and I’ve also been impressed by the strong edge support which means I can stretch out without feeling like I might slide off. My partner hardly notices when I move around, which has made a real difference to how undisturbed our sleep feels. It also stays pleasantly cool, even on warmer nights.
Firmness and pressure relief
The mattress sits within the medium-firm range, which for me is ideal – supportive enough to keep my back aligned but still cushioned under my shoulders and hips for when I side sleep. Compared to my old memory foam mattress, it’s liberating: I can move freely without feeling “stuck”, yet I still get that gentle contouring that relieves pressure.
As a combination sleeper, this adaptability is invaluable. Whether curling up on my side or stretching out on my back, the mattress adjusts instantly. My partner, who prefers a firmer base, also finds it comfortable. Together, we’ve noticed a huge improvement in how undisturbed our sleep is, thanks to the minimal motion transfer. The medium-firm feel may take some getting used to if you’re accustomed to ultra-soft mattresses, but for me, it’s the ideal zone of comfort.
The 5,750 individually pocketed springs are not just a bragging point – they genuinely contour to your body in every position. For side sleeping, the mattress cushions my hips and shoulders without letting me sink too deeply. On my back or stomach, it keeps my spine aligned perfectly.
Edge support
The edge support is another area in which the mattress excels. I’ve been able to sleep close to the edge without feeling like I might roll off, which is a huge relief for someone like me who tends to sprawl out at night. Overall, it combines firm support with just enough “give” to relieve pressure.
Motion transfer
The mattress is brilliant for couples. I move around constantly, changing positions throughout the night, yet during testing, my partner said he rarely felt a thing. Even if someone gets up to use the bathroom or stretches across the bed, the pocket springs absorb movement so well that it doesn’t disturb either of us. For anyone sharing a bed, this makes a massive difference to overall sleep quality.
Temperature regulation
One of the standout features for me is how well it handles temperature. The natural layers (made of wool, cotton, and hemp) have kept me comfortable across both warm and cooler nights. I haven’t felt trapped in heat like I used to with memory foam, and even on unseasonally warm evenings, the mattress breathes well. There’s a sense of freshness and dryness that makes it feel cosy without ever being stifling.
Maintenance
The grassington 5750 is low-maintenance but does require some care. Its weight means rotating it is a two-person job, but that’s a minor trade-off for a mattress this durable. The cover can’t be removed, but it can be spot-cleaned, which is great for keeping it fresh, and the natural fibres resist dust and allergens. Over the months of testing, I haven’t noticed any sagging, soft spots, or odour, which reinforces the impression that it’s built to last. Regular rotation (every few months) helps maintain the shape, but flipping isn’t necessary thanks to its construction.
Buy now £1609, Mattressonline.co.uk
Your questions about the Harrison Spinks grassington 5750 pocket mattress answered
Is the Harrison Spinks grassington 5750 pocket mattress worth the money?
The Harrison Spinks grassington 5750 pocket mattress is a great choice, especially for someone like me who changes positions constantly throughout the night. Whether I’m on my back, side, or sprawled out on my front, it adapts effortlessly, providing support without feeling too firm or too soft. It has great breathability and I also love that the overall build feels premium and durable, so you’re getting what you pay for here.
If you’re a combination sleeper or simply want a mattress that balances support and comfort across all positions, this is an excellent choice.
What are the disadvantages of the Harrison Spinks grassington 5750 pocket mattress?
While I’ve really enjoyed sleeping on the grassington 5750, it’s not without a few minor downsides. For one, the mattress has a slightly “bouncy” feel due to its 5,750 pocket springs, so if you’re used to the slow, enveloping hug of memory foam, it might feel firmer and more responsive than you expect. As I’ve said, it’s also a heavy mattress, so moving or rotating it definitely needs two people – something to keep in mind if you like to rearrange your bedroom frequently or live alone.
Finally, it sits firmly in the medium-firm category, so anyone who prefers a very soft, cloud-like bed might need a little time to adjust. For me, the balance between support and cushioning has been perfect, but it’s worth knowing these points before you take the plunge.
Why you can trust IndyBest reviews
The Independent’s dedicated shopping section, IndyBest, is committed to providing unbiased reviews and expert advice. Sarah Jones has years of experience testing all manner of sleep products – from duvets to mattress toppers – so she’s well versed in the language brands use to make bold promises. She knows how easy it is for marketing to oversell the dream of “perfect” sleep, and approaches every claim with a healthy dose of scepticism.
Sleep is something she prioritises above almost everything when it comes to her wellbeing – not always simple as a parent of small children. She’s also had her own challenges with getting consistent, good-quality rest, including periods of back pain following surgery, so proper support and comfort aren’t abstract concepts to her. As The Independent’s resident sleep expert, Sarah knows the best, most comfortable fabrics and materials to look for in mattresses and bedding and has a strict criterion by which she judges each one.
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