Depends on the type of foam you're using from mycasebuilder.
If using Ester Foam, which is the type of foam you most see used for Pick-n-Pluck foam, the spacing style will be worthless as the foam is soft. The areas of foam dividers will fail after minimum use. I've moved away from soft PnP type foam all together.
If using the PE Foam (Polyethylene hard cell) the spacing style works fine and will not break down over time.
I've never used the Pro Cell foam so I can;t comment.
I use spacing when storing chips without racks. When storing in racks I use the merged method, but I only use the PE Foam anymore.
with spacing