Hi ok11,
This was explained to me by Brooklyn Bedding a while ago as a more accurate (and conservative) representation of the density of their polyfoam cores. They were finding their cores in the 1.7 lb range, but to their credit, put the listing at 1.5 lb (even though the 1.7 would fall within the “bucket” of ILDs to rate the core at 1.8 lb, which many manufacturers opt to do). Basically, more of an “under-promise/over-deliver” philosophy.
If you go back and read through this thread or do a search on the forum, I’ve tried to be quite clear in my thoughts about the Arctic Dreams representing one of the better values in budget-priced foam mattresses. Overall, it’s a great quality/value choice, but you are the only one that can decide whether it’s the “best choice” for you in terms of personal preference, quality, application and durability, and all the other parts of your personal value equation that are most important to you (including the price of course and the return/exchange options you have available after a purchase if the mattress doesn’t turn out as well as you hoped for).
And you’re correct, I don’t believe they list the foam density on their web site for this particular polyfoam core.
Phoenix