Hi justatypicalfool,
The first two numbers are the density of the polyfoam (2.4 lb which is good quality polyfoam) and the last two numbers are the IFD which is the firmness level of the layer and similar to ILD in latex (although they are not directly comparable). While latex is a great material … different designs and layer combinations are part of what makes a mattress more or less suitable for each person in terms of PPP (Posture and alignment, Pressure relief, and Personal preferences). If objective and careful testing indicates that a particular design isn’t suitable for your needs and preferences, then no matter what material is used or its quality and value, it would have little value to you. I would certainly choose a good quality latex/polyfoam hybrid over an all latex mattress that wasn’t the most suitable design for me.
I would talk to them on the phone to “demystify” their options and terminology and let them know what you have tested and preferred so you can make meaningful comparisons. Phone conversations (or face to face conversations in person) are always one of the most important parts of making informed choices.
The better options and possibilities I’m aware of in and around the Greensboro / High Point area are listed in post #2 here.
It’s always great when you have at least one good quality / value mattress that is suitable for you as a reference point to compare others against and your “worst case” is already a good choice 
Phoenix