Hi Starálfur.
I would be surprised if you had an issue with sleeping temperature in this mattress. Latex in general is more breathable than other types of foam and the quilting they use in their cover is also very breathable. Latex in general is also more resilient than other foam materials (such as polyfoam) so it would depend on what you are comparing it to although it’s true that Talalay is more resilient than Dunlop.
I would be very cautious about using reviews as a reliable source of information or research (see post #13 here) because in many if not most cases they can be more misleading than helpful (either positive or negative). They did change the support core in their Talalay latex mattress a few years ago but the new material is a higher performance material than they were using previously and the lower density would only make a meaningful difference in terms of durability for those that are in much higher weight ranges than you are. For many people the new materials would be a better mattress. You can read some more detailed comments about this in post #14 here and their comments about their base foam in post #4 here.
I can certainly understand the temptation of second guessing good choices but once you receive your new mattress you will know for certain how it feels and performs for you and I think that the odds are high that you will be happy with it (and you also have several configurations that can change the comfort and support of the mattress as well if you need to).
I’m looking forward to your feedback once you receive it.
Phoenix