Product review (4 stars): Keeps the odd bits from falling in the crack
Update 10/12/16:  I'm still happy with these.  The only sign of wear is a little discoloration from the heat of the stove in some places, but it's not a big deal. Still easy to clean and does it's job.

I actually thought these would be a bit stiffer.  Not that it matters I suppose.  They do the job of keeping bits of food and stuff from falling between the counter and stove.  It occurred to me that I needed something like this when I dropped a chunk of raw potato down in the crack.  I can't fit the broom or vacuum hose in the crack to clean it out.  If you've ever abandoned raw potato in the house, you know that in a week or two there is a truly nasty smell that will accompany it.  Well, after making soup last night, and transferring various veggies from the cutting board to the pot, I can tell you these seam protectors work.  They handle high heat well without melting since they're made of silicone.  I've included pictures of my stove to counter crack with the protectors flopped on the stove top.  My counters suck as they were a homemade job by some previous owner and I haven't been able to have them redone yet.  Don't judge.  You can see how white the seam protectors are, how much they cover and what they look like from various angles.  They clean easily.  The downside is they move around a bit, but that could be because my stove isn't level with the counters.  Since they are so lightweight, it's easy to move them to wipe underneath.  I can't wipe from counter to stove going across the protectors though because they won't stay in place. If they were a bit stiffer I think it would work better.  But as long as it keeps hidden potatoes from stinking up my kitchen I'm happy.