Hi jwblue,
Thank you for your inquiry and the information provided!
Hopefully a few others will comment if they are familiar with the products you described. However, your decision should be based on your own personal needs and preferences. How a product feels to another person would be their own experience and this person could be very different from you in terms of height/weight, sleeping positions, mattress preferences (plush vs rock hard), and other factors. Ultimately your latex purchase should be based on your own PPP. It may be helpful to read this post here. Also, if a mattress is a good fit for you in terms of PPP, keep in mind that a mattress is only as good as the quality of the materials inside. This article here is a good reference to explore the quality and durability of the mattress and if it has any weak links in terms of its design.
Our company sells layers of latex in our mattresses and also allows customers the ability to exchange a layer for a new one. As someone who has worked at our company for 5 years and processes most of our swaps, I wouldn’t conclude that customers typically swap for a firmer or softer layer majority of the time. It is about an even mix. I would say, however, it is easier to make a firmer mattress become softer (with mattress pads, toppers, etc.) than it would be to make a softer mattress become firmer. If a mattress is too soft, it would not provide proper alignment and it would be hard to correct a mattress that is unsupportive.
Hope that helps!
https://uploads.mattressunderground.com/outside/40660/128x84_fsf_logo.jpg