Why our sleep experts loved it
I've trialled this mattress at my local Furniture Village store and it is one of those mattresses that instantly feels like it was built for back sleepers. If you like firm, unwavering support and don’t want the heat of traditional memory foam, this one feels custom made for you. It is deep at 30 cm, reassuringly heavy and finished with a cool touch fabric that actually feels fresher to the hand. It’s an expensive bed, but the specification and real life performance tell a compelling story if you need proper alignment and are on the firmer, more stable side of bed preferences.
Construction & Materials
This is a hybrid design with a traditional pocket spring base paired with a plush pillow top topper containing mini springs, a layer of memory foam and Sleepeezee’s Dreamzone gel foam. The core uses traditional rows of pocket springs and has high density support layers both above and below, while the pillow top topper adds a softer comfort layer before the Dreamzone gel foam and mini spring systems come into play. The cover is a cool touch knit fabric. Headline numbers are excellent. The quoted spring count is 4300, all in full height pockets but including the responsive mini units, with that all set in a depth of 30 cm. This is a single sided mattress so the pillow top is always on show and you will rotate rather than flip.
Firmness & Feel
This is rated firm and it absolutely lives up to that in practice. In fact out of the box it actually felt a little rigid in the mid section and needed a few nights to settle down and reach a supportive but slightly buoyant feel. The pillow top layers take the edge off the overall firmness and you are not really lying on a board, but it is not a deep sink mattress and really is on the firm side. On my back the Dreamzone gel foam has good shaping ability in the lower back without being an engulfing mass of squish. The mini springs help keep the surface lively and responsive while still delivering good support and there is the option of side sleeping if you like that and can take the shoulder feel, although lighter bodies may find the overall firmness a little stiff in the shoulder and hip. Front sleepers who prefer a flatter, more level surface should get on well.
Performance & Support
I was really impressed with the spinal alignment on my back. The twin spring construction gives the core proper authority so the hips don’t sag and the lumbar region is well supported. Pressure relief is better than you might expect from such a firm mattress due to the pillow top and Dreamzone gel foam but this is still a supportive bed first and foremost. Motion transfer is well controlled for a spring bed, the combination of mini springs and foam layers taking the sting out of partner movement without that dead, stuck sensation you can get from an all foam design. Edge support is very good and stood out. Sitting or sleeping close to the side felt stable and there was no roll off nudge you can get from some deep pillow tops.
Temperature Regulation
The open spring architecture, a cool touch cover and the Dreamzone gel foam do a great job of keeping things noticeably cooler than a like for like memory foam hybrid. I run warm and I never felt heat building anywhere, whether round the shoulders or hips. It is not ice cold by any means, but reliably neutral, which is exactly what most warm sleepers need.
Practical Features
This is a 30 cm deep mattress with substantial fillings so it is a heavy bed and you will need two people to handle rotations. It is single sided and as such requires regular rotation rather than flipping. The cover is a cool touch knit that feels like it would be quite durable but this is not a removable machine washable cover so you need a protector on day one. Platform bases and sprung divans are ideal but will work with a slatted frame so long as you check the gaps are no wider than 7.5 cm to protect the guarantee and not compromise support.
Who It Suits
Back sleepers who like firm support: excellent mid body lift and clear lumbar support.Hot or warm sleepers: cooler than standard memory foam hybrids thanks to the gel foam and airflow through the springs.Couples: good motion control for a spring bed and the edge support is so strong it makes the usable surface feel larger.Heavier builds: the robust spring unit resists dip and sag while maintaining alignment.
Who It Doesn't Suit
Plush mattress fans: if you want marshmallow levels of cuddle and deep slow sink, this is not it.Petite side sleepers: the firm rating may make this feel too hard on the shoulder and hip.Natural purists: this is a very modern hybrid with foams and a cool touch knit rather than natural fillings.Bargain hunters: it sits at the upper end of the market, so value is tied to how much you need the firm support it provides.
Final Verdict
The Sleepeezee SensaGel 4000 is a deep, luxurious feeling firm mattress with a big focus on where it counts for back sleepers, including alignment, temperature regulation and edge stability. The Dreamzone gel foam provides gentle contouring without heat retention, the mini springs add welcome liveliness and the core keeps everything aligned and true. It is not a cheap option but if you are a back sleeper and like the idea of a high quality, cooler running firm mattress, you will struggle to do much better.
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