Product review (5 stars): I love them and wish I had bought them years ago
These totally solved my "stuff falling between the stove and counter" issues.  I love them and wish I had bought them years ago!  Like all silicone, though, they do have a heat limit.  I don't know exactly what it is, but my husband used my large pressure canner one day, which partially hung over the silicone (not sure how he managed that, but he did).  The resulting heat melted the edge of one of the seams, and when it cooled, it resulted in an off-colored, hardened, and cracked appearance.  It still works, so I haven't replaced it, but I am more careful now to move it back a bit when I turn the canner on.  Otherwise, it's fine.