The coils have nothing to do with heat retention. This design has been used and failed numerous times over the years. The single coil is stronger than two half coils....a well established fact.

I am well aware of the history of coil-on-coil structures, and have quite a few years experience selling them. Simmons did have coil-on-coil in their WorldClass Exceptionale models (remember the "Summit tops"?), and Stearns and Foster had their "Pillow Coil" a couple of years back . It was the cushioning layers that tended to fail on these beds, not the coil system, in my experience. My only concern with structures like this is their compatability with adjustable base systems. Simmons says they are OK, but I have some concerns there, as does my local independent mattress inspector...

Generally speaking, I am not a huge fan of any innerspring unit. I believe that newer technologies trump springs in virtually every measurable way (strength, flexibility, quality of pressure relief, motion seperation, etc).

In all seriousness, if you do have real information about the history of coil-on-coil structures failing, I would love to be better informed...

-Scott

Since the double-stacked coils tend to be a lighter gauge of steel, I would question the longevity of this type of product; especially if you're spending thousands on a mattress.

In a dual layered encased coil design, the top layer usually provides comfort and the botton layer provides support. These designs provide long lasting and highly comfortable sleep. These designs also provide more "breathable" and less-hot and less-sweaty sleep.

I would have to agree that the dual coil system is more breathable, conforming and durable. We have been handcrafting our finest model called "The Yarmouth" for over 8 years which has over 2,000 coils in queen. Microcoil paired with Talalay Latex foam giving it a very flexible and lightweight feel that customers rave about. We've had clients from all around the world who have slept on our mattresses at Bed and Breakfasts in the Berkshire's order them. Bottom line: Steel is stronger than foam... Now THATS a fact. I'm a little skeptical of your source that has proven this design a failure.

NN