Hi Random.
Welcome to our Mattress Forum. 
There is more about the different types of latex allergies or sensitivities in post #2 here but in most cases (unless you have a more severe type I allergy and carry an epipen) a latex allergy isn’t an issue with the type of latex that is used in mattresses and because there is no actual contact with the latex itself.
Since you do mention a type 1 allergy, it’s probably worth being concerned.
Latex can be a great alternative to memory foam if you dislike the way memory foam tends to “collapse” in on itself as it heats up throughout the night. But, a high density, durable memory foam is also amazing!
Buckling column gel isn’t high on my list of favorites/recommendations. It’s still a fairly new material that isn’t well studied and really seems to be most useful for people with extreme or intense support needs.
While not a member of our Trusted Member listing, you might want to consider the EOS Classic from Naturepedic (totally latex free). It’s fully customizable and allows for split layer customization as well for you and your husband’s mixed needs. It has a separate comfort layer so that you can swap it out later if you find your comfort or support needs change. It’s a pretty comprehensive mattress and one of the only latex free, non-synthetic options of its kind.
It’s definitely a worthy contender, in this case! And in general, Naturepedic does a great job creating quality beds.
If you come across options you’re considering that you’d like us to help evaluate, we’re happy to do so!
NikkiTMU