FWIW if you have any trouble getting the foam (or foam plus topper) back into the covers, which may have shrunk up a bit, try putting a large trash bag over the foam, with the open end faving in and the bottom facing out. The covers slip right over the plastic, and then you can pull the plastic bag out leaving the foam tightly tucked into the cover.
The canvas came pretty clean...so I'm happy with that.
But the foam still smells a bit funky. I soaks them in vinegar and water...thought that may work as I read it somewhere here...not good enough. Anyone ever try bleach to remove the mildew smell?