Hi wendym,
I noticed that you registered with your email as your username which means that automated spambots will be able to harvest your email and add you to their spam lists. If you’d like I can remove the @ and the domain after it and change your username to just wendymlevin (or any username you wish).
The single biggest factor in the durability of a polyfoam material is it’s density not thickness or the surface area of the mattress.
Both the Ultimate Dreams latex and the Ultimate Dreams Eurotop use the same density polyfoam in their base layer and both have the same 3" thickness of Talalay latex in the top layer and when you are in a higher weight range then you will tend to “go through” the top layer more and compress the support layer more deeply which means that it’s density would play a bigger role in the durability and useful life of the mattress than it would for those that are in lower weight ranges. The main difference between the Eurotop and the Ultimate Dreams latex is the options you have available after a purchase to exchange the firmness of the latex comfort layer (in the case of the Eurotop) and if you are using the same firmness latex in the comfort layer in both of them then their durability would be closely comparable.
As you can see in the guidelines here … in your weight range I would consider a higher density base layer in the range of 2 lbs or higher.
It may also be worth considering the Ultimate Dreams Natural which uses a Dunlop latex comfort layer with a 2 lb base layer or the new Brooklyn Bedding mattress (Brooklyn Bedding is a sister company of Dreamfoam) which uses 4" of latex (2" of blended Talalay latex and 2" of synthetic Dunlop continuous pour latex) on top of a 2 lb base layer as well (and also has a free return policy). You can read more about it in posts #6 - #10 here and in post #3 here.
If you are referring to the Aloe Alexis then it uses two 3" layers of latex instead of one and also has a 2.17 lb polyfoam support core so with a total of 6" of latex instead of 3" it would be closer to the feel and performance of an all latex mattress than either the ultimate Dreams latex or the Eurotop and it would be more durable as well (see post #2 here and post #2 here). It also has wool in the quilting which would be more temperature regulating and it also has the option to rearrange the top two layers or change the firmness of either of the two latex layers so it has more flexibility to fine tune the feel and performance of the mattress than either of the other two you mentioned but of course it is also more costly because it uses higher quality and more costly materials and components and contains twice as much latex.
Phoenix