Hi rose24,
Flexus is one of the members of this site which means that I think very highly of them and they compete well with the best in the industry.
A forum search on “Flexus” (you can just click this) will bring up more information and feedback about them as well.
The foundation post here and the two posts it links to in the second paragraph has more information about and sources for foundations or other support systems that are suitable for different types of mattresses including latex. While they may be durable … you can see my thoughts about the wire grid type of foundations I think you mean in post #10 here.
Phoenix