Hi AJohnson,
I’m happy to hear that Dreamfoam has been helpful to you. And I don’t doubt that adding the extra memory foam on top of your current Arctic Dreams made it too soft for your preference.
Regarding Zinus, I would also read post #6 here about mattresses imported from Asia or China and which may have been compressed for long periods of time in either shipping or storage before being purchased and a forum search on Zinus (you can just click this) will bring up more information and feedback about some of their brands and mattresses, and being sourced in China would make this somewhat of a risky purchase IMO.
The Energex compresses at a different rate than the polyfoam in the Addable, and without getting into too much detail, ILD is not the most reliable indicator of how soft or firm a layer will feel. Compression modulus is even more important because very few people actually sink into a layer exactly 25% and compression modulus is the rate at which a foam gets firmer as you compress it more. And the polyfoam layer will firm up at a different rate than the Energex.
Trying to predict how a mattress will feel and perform using only one of many “specs” or variables that are involved can be somewhat risky or misleading and even the most experienced mattress designers that are familiar with and have a great deal of experience with all the many variables and specs that can affect the feel and performance of a mattress can often be surprised at what a mattress was “supposed” to feel like based on specs and what it “actually” feels like in real life so in practical terms the only reliable way to know how any specific combination of materials and specs will feel like for you would be based on your own actual testing or personal experience. Specs can be a very rough guideline that can help you “find the range” but there are far too many unknowns and variables to use them to find the “best” combination or materials or components that would be suitable for any specific person with any degree of certainty.
Like Dreamfoam, Addable is a site member here, which means I think highly of them, so if you do choose to select their mattress I’m sure they will provide you excellent service along the lines you’ve received from Dreamfoam.
Phoenix