Hi tull2001,
The OMF Serenity uses two layers of blended Talalay latex on each side of a polyfoam core. The top layer of blended Talalay is about 19 ILD and the second layer is about 24 ILD. They don’t say what the thickness of each layer is or the total thickness of Talalay on each side (I’m not sure if the total thickness is 2.5" or 3" based on the differing descriptions in post #1 here and post #6 here). If I had to guess I would guess that each of the two layers are a total of 1.5" for a total of 3". If the latex layers on each side are 3" then the polyfoam in the middle would be about 4" - 4.5" and if the latex layers on each side are 2.5" then the polyfoam in the middle would be about 5" - 5.5". The density of the polyfoam support core is 2.5 lbs which is high quality polyfoam. The polyfoam is in the range of 26 - 34 IFD. The cover is a stretch knit. NOTE ADDED: The thickness of both layers combined has been confirmed at 3" and the top 19 ILD layer is apparently 1" and the second 24 ILD layer is apparently 2".
The Dreamfoam has a 3" layer of blended Talalay latex (the same as the OMF) and you can choose the firmness level. The base layer is 1.5 lb polyfoam but I don’t know the IFD (it’s probably in the same range). The cover is quilted with 1.5" of polyfoam.
As you can see … the design of each mattress is quite different and every layer in a mattress has some effect on the feel and performance of the other layers and the mattress as a whole but the 3" blended latex they both use is the same material.
Phoenix