Hi waxteeth,
What I actually have from the bottom up is a 1" layer of "stabalizing foam", 6" of firm latex, and a 5" layer of the medium. What I've been told is that the original composition was too wobbly and changing things up by removing an inch from the top layer and installing the one inch stabalizing layer of (what I can best tell is some natural HD foam) sigificantly improved the feel of this bed.
This is certainly a valid argument and there are several reasons that a very firm "stabilizing" layer is used under latex. While the necessity depends on the specifics of the mattress including the type and firmness of the latex layers, the thickness of the latex, the cover, and even the body type of the person on the mattress, a stabilizing layer of firm polyfoam (typically 1" to 2") which is stiffer than latex can reduce side to side sway in some thicker latex mattresses and it can also help prevent damaging the latex when it is being handled in the factory (latex tears easily when it is grabbed or pulled) and protect the latex from damage over time with some types of foundations such as slatted foundations that have wider gaps or that have a "wire grid" surface. For some people who want to avoid polyfoam completely it can create a "negative" perception having polyfoam in a mattress (which some people wish to avoid completely for personal reasons) even though it can be beneficial in some cases.
A layer of firm polyfoam that deep in a mattress would have no effect on durability or on the pressure relief or support of a mattress ... especially if there are 11" of latex on top of it.
Is there a point where all latex is too much and gets wobbly?
Again ... this depends on the specific construction and design of the mattress and on the body type and preferences of the person on the mattress. Some people "feel" that latex is too wobbly or "jiggly" even with thinner layers or thinner mattresses while for others it's not an issue at all and the "response" of latex is part of why they prefer it. Talalay can be a little more "jiggly" than Dunlop and softer latex will be more prone to this than firmer latex.
To be fair I've only had this bed a few hours and have never slept on it. My first feeling was simply to return it because it isn't what I bought and paid for. After talking to the owner and hearing his explnation it sounds reasonable enough but 1) I intentionally got away from foam base with latex on top so seeing even the 1" in there aggravated me. 2) in my mind 12" of latex was better than 11" and my gut feeling was that I got ripped off for an inch of "the good stuff".
In terms of PPP (outside of the effects of the stabilization layer) or even "value" there would be little difference between having 11" of latex and 12" of latex although of course complete disclosure and knowing what is inside your mattress is always important so that what you are told is in your mattress is what you actually receive and you can make more informed choices.
Perhaps this set up is actually better it just isn't what I was expecting and am looking for opinions on the above. I did start to notice there are not a ton of other beds out there with this much latex in them and there are a lot around 10"....maybe there is a reason.
There is more about the potential "benefits" of thicker layers or thicker latex mattresses in
post #14 here
but in most cases there isn't really a "need" for more than about 8" or 9" of latex unless you are in a heavier weight range although it may still be a preference for some people depending on the specific design of a thicker mattress.
I know one manufacturer who sells quite a few 15" latex mattresses in his showroom because so many people prefer it when they test them in person over the thinner models (in spite of the higher cost) even though it's not as popular with online sales where cost is usually a bigger issue and they can't "feel" the difference. Even though a certain feature of a mattress may not be "necessary", it can still be a preference if people who test them consider the difference in how it feels and performs to be worth the extra cost.
Phoenix