Hi jwind55,
The topper guidelines in post #8 here may be helpful in choosing a suitable topper.
How well a mattress matches your individual needs and preferences is of course an important part of its value (as long as you have tested the mattress carefully and objectively using the testing guidelines and not just tested for the “showroom feel” or subjective “comfort” of the mattress) but a mattress is also only as good as it’s construction and the quality of the materials inside it so knowing the thickness and specific type and quality of all the materials and components in a mattress is a key part of an informed mattress purchase. It’s especially important to know the type and quality of all the foam layers above the coils because without this information there is no way to make meaningful quality or value comparisons between mattresses or identify any potential weak links in terms of durability. A mattress will soften and break down from the top down and the loss of comfort and support that goes with the early softening of lower quality materials in the comfort layers is the main reason people need to replace their mattress and the loss of comfort and support isn’t covered by a warranty.
It’s the job of the salesperson to provide you with this information (or phone the factory if they don’t have it) but it’s also not likely that the salespeople at the Bay know very much about how to identify good quality materials and may be little help in educating you about the quality of either mattress. If you can provide the details of all the layers in both mattresses from the top down including the thickness of each foam layer, the type and density of any memory foam or polyfoam, or the type and blend of any latex in the mattress and post it here I’d be happy to help you identify any potential weak links in the mattress or make more meaningful comments about either of them. Without this … the only information you have is the brand of the mattress or a few of the less meaningful specs which really don’t mean anything.
The gaps in your foundation look fine (under 3") for use directly under a mattress although the thinner slats look like they’re thinner and lower than the wider slats and I can’t really see the details of the center support so hopefully this is good as well.
Phoenix