Hi BruceM,
Sleepez uses Dunlop for support and Talalay for comfort and does not glue their layers together allowing more options for constructing the perfect mattress for each customer.
SleepEz actually allows the choice between Talalay and Dunlop and different ILD's of each in each of their layers. I believe that all talalay is probably their most popular choice.
MyGreenMattress.com uses layers of Talalay glued together. By not gluing the layers together do you not open up to the possibility of shifting or "bunching" over time
This could happen to some small degree but with a zip cover it is very easy to "fix" if it does happen. Latex is very "'sticky" so it doesn't have a tendency for one layer to shift over another as much as other materials. On the other hand ... with a finished mattress .. gluing the layers together is IMO a better idea because the layers in the mattress can't be accessed and it creates a more integrated unit and removes any possibility of shifting. Each has a benefit and a downside as part of the "tradeoff".
does Talalay work as a support layer were it is more for comfort and not as dense as Dunlop? Your thoughts please and thanks again for the help.
Talalay in firmer ILD's works very well for a support layer and it is a much higher quality support layer than other materials such as higher quality HD polyfoam used under many mattresses (such as the Tempurpedic). It is also available in a wider variety of ILD's than Dunlop. It is different in it's characteristics and "feel" though from Dunlop which gets firmer faster than Talalay but neither one is better than the other in terms of a support layer. They just are part of different designs used to create different feels and qualities. The differences are more a matter of preference and while the differences can be used to "design" different mattresses ... one is not better than another.
It's probably true that more people prefer Talalay in the comfort layers because it has softer options than Dunop but this is by no means universal and many prefer the more "on" the mattress or less "springy" feel of Dunlop. In support layers though, you will find a wide variety of different individual preferences between them with some preferring one and some the other.
Phoenix