Hi BobP,
I have no doubt that these types of foundation are strong enough to hold a latex mattress but my concern would be more for its long term effect on any latex in the bottom layers of the mattress and in the case of 9.5" gaps the short term as well … with or without a fabric cover. My concerns have come from talking with manufacturers who have many years of experience with latex mattresses and have seen the effects of larger gaps in a support system on latex mattresses… even with wire grid foundations that have smaller gaps or spaces and a more evenly supportive surface area. I wonder if they have tested their foundation with an all latex mattress over a period of 5 - 10 years and evaluated how it performs in real life over the longer term.
You can see more of my thoughts in post #10 here (and some possible solutions) but I would personally tend to avoid these just because it makes sense to me that the risk would be much higher than other types of foundations and in this case with the larger gaps even higher than other types of wire grid or metal foundations.
I’ll also be interested in seeing the design of their new model and it seems to me that just the fact that they are introducing may be an implicit recognition of the very issue we are discussing.
Phoenix