Hi lookingforsleep44,
The issue with these types of these types of wire grid foundations (besides the fact that some of them seem to squeek but this may be fixable depending on where the squeek is coming from) is that the ones that have less longitudinal wires in them also have wider spaces in between the wires and that this can create the risk of the foam sinking into the spaces between the wires over time. In general … the ones that have more longitudinal wires and smaller gaps are “safer” but sinking through the gaps is a bigger risk with a latex base layer than it would be with polyfoam which is stiffer. Either way though … the larger the gaps are to sink into and the less surface area that supports the mattress, the greater the risk that the foam will sink into them over time.
The manufacturer themselves are usually the best source of information about whether a foundation would be suitable or meet their warranty requirements and you can see some of their foundation suggestions ADMIN NOTE: Removed 404 page link | Archived Footprint: How to Buy the Perfect Foundation for a Latex or Memory Foam Mattress - Brooklyn Bedding.
As you can see they don’t recommend box springs … only rigid non flexing foundations (which are generally better for foam mattresses than a box spring which has springs in it).
Other suggestions are in the foundation thread here.
If the price is a bigger priority than the support of the foundation then these are probably an acceptable choice (and again the final “authority” is always the manufacturer) but I would personally spend the few extra dollars to buy a less risky version with smaller gaps between the wires.
Phoenix