Hi tismon,
thanks for the feedback 
With Talalay a difference of 2 ILD would be undetectable and would also be within the tolerance of the manufacturing process itself (which is about +/- 2 ILD). The reason for the wider range with SleepEz is because they carry Talalay made by two manufacturers not just Latex International.
With Dunlop there is a larger variance of ILD both in a single core (which can have a larger variance across the surface, between the top and bottom of a layer, and between individual layers that have the same rating). ILD in Dunlop is not as accurate as with Talalay (see post #6 here) so the ones that you are rating as “possibly softer” or “probably firmer” may also be the other way around depending on the specific layers being compared.
I think in most cases since ILD is not exact anyway their “word ratings” would be fairly comparable and would be “close enough” for the majority of people (assuming you are comparing the same type of latex).
The specs and ILD’s of the Pure Latex Bliss blended Talalay latex mattresses are listed in post #2 here.
Phoenix