Hi G671,
The choice between latex and memory foam is a preference issue and some people much prefer latex while other people would much prefer memory foam. Either way … the design of the mattress and how well it matches your body type, sleeping positions, and preferences in terms of PPP would be important because any materials can be used to make a mattress that will work well for one person and not the next. You can read a little more about the differences between latex and memory foam in post #2 here but the best way to know which one you prefer is your own personal testing.
Hopefully you’ve read the tutorial post here which has all the basic information, steps, and guidelines that can help you make the best possible choices. The two ways to choose a mattress in terms of its type and design so you can find out whether it’s a good match for you in terms of PPP is either with your own careful and objective personal testing or if that’s not possible through more detailed conversations with the manufacturer (see mattress firmness/comfort levels in post #2 here) in which case the options you have after you have tried a mattress and slept on it in person (to exchange the mattress or individual layers) may also be an important part of your personal value equation in case your actual sleeping experience indicates that the mattress isn’t the ideal “match” for your specific needs and preferences.
Both of the manufacturers you are considering are members of this site which means I believe they compete well with the best in the industry in terms of their quality, value, and service and they would both be well worth talking to.
Phoenix