Hi pgardella,
It would certainly make a difference yes but what kind of difference would depend on how both of you like the feel of latex and also on how the latex compares to the firmness of the polyfoam you currently have. Even a high quality polyfoam in a different firmness level (or that didn’t have any sagging which I’m assuming yours does) could make a significant difference. It would also depend on the reasons behind your wife’s aching back or shoulders and whether a replacement layer would “correct” the underlying issue.
[quote]It’s 1/5th to 1/10th the price of a new bed. Or do a split topper to select the softness of the comfort layer (although that adds 50% to the cost of the topper).
Thoughts? [/quote]
Assuming your air bladders are still in good condition and that the reason for your wife’s “symptoms” aren’t with the response or any sagging with the air bladder itself (or its firmness setting) I think that “in theory” a replacement layer would be a good idea. The worst case is that if you were to replace the mattress with a component mattress then you could still use the layer you purchase in the new mattress. Because you probably have a fairly large weight differential I would be tempted to go with a split layer (assuming you have a king size so that two twin XL layers will fit).
There are some topper guidelines in post #8 here that may be helpful and it also links to a list of some good sources for different types and blends of latex layers as well.
Phoenix