Hi rictorjr,
This is not an unusual comment when you use Dunlop in between Talalay layers because of the differences between the two types of latex (see post #7 here) and while any combination of layers can work well or be a preference for some people … it would be more common to use Dunlop either in the bottom layers or on top (depending on different people’s preferences) rather than in between Talalay layers.
I’m not clear on the difference between this and the combination in your first post which appears to be the same. I thought you had already tried the 3" layers with both of them on top.
It’s not really possible to know until you sleep on it because of all the variables involved and your sensitivity to smaller changes but a 3" layer of @25 ILD Dunlop and a 3" layer of @28 ILD Talalay will be “somewhat” similar in terms of firmness but because of your experience with 6" of “softer stuff” on top which didn’t seem to work for you in either combination it may be worth considering a little less thickness in the transition layer to keep you closer to the firmness of a higher ILD support core.
I would probably only make one change at a time as well so that you can evaluate things “one step at a time” rather than trying to figure out the combined effect of two different changes (the 3" layer and the support core firmness) which can be more difficult to assess.
Phoenix