GoKawiilFirm mattresses are often considered the gold standard for improved spinal alignment, even weight distribution, and overall support. As a certified sleep science and brain health coach, I’ve been on this particular soapbox for a long time.
I’m one of several WIRED reviewers who deal with back pain and who champion the benefits of a firm mattress. However, one of Sleep Number’s newest offerings, the ComfortNext Lux, has changed the way I look at softer beds.
The Reboot
Photograph: Julia Forbes
There have been many changes at Sleep Number lately, starting with the reorganization of its offerings into three collections: ComfortMode, ComfortNext, and Climate. Within these collections are five new mattresses, with the ComfortNext Lux as the mid-tier newbie from the ComfortNext line.
The premise of this new line is upgrading pressure relief, cooling, and general support. You’ll still get the hallmark features of a Sleep Number bed, which include intensive sleep tracking from the bed itself, and 100 firmness levels at your fingertips via app connectivity. You’ll also have a range of motion for the bed's top and bottom, along with settings like zero gravity to reduce pressure on the spine, provided you have an adjustable base—more on that in a minute.
Squish Factor
With smart beds, the ability to adjust firmness levels depends on an internal air chamber. It inflates to become firmer or deflates to become softer. Many smart beds will incorporate a few thinner layers of foam to be a buffer between you and the air chamber. That is still the case with the ComfortNext Lux, but the softness is quite prominent due to a thicker layer of foam on top. There is an easy 3 to 4 inches of sinking to be had here, depending on your build. I was also surprised to discover this bed uses micro coils, something I’ve never seen in any smart bed from any brand.
In my over six years of mattress testing, I haven't found micro coils to be a life-altering mattress material. They simply add structure to a mattress, especially one with three or more layers of foam. To this end, they provide better support across the surface, so you don’t sink through all these layers. Usually, I can’t detect micro coils, but with the ComfortLux’s softer surface, they made all the difference in maintaining full-body support. Without them, this mattress would have been an absolute marshmallow.