Product review (5 stars): Fits snugly
Fits well, have a narrow gap between stove and counter on both sides, < 1/2 inch and these fit well.

Pros:
- Does what is should, keeps the crumbs out.  I cleaned the sides/bottom of my oven before installing these and... yuck, might be crumbs to us but a feast to La Cucaracha!  You know the usual stuff, like that milk or oatmeal that boiled over and ran down the side, grease from frying and splattering, grains of rice, etc. (even though we do the usual Spring cleaning).
- Easy to cut to fit, appears some negative reviews were due to size but appears that was before they had 21 and 24" options.  My stove is 21 and fits nice, in fact had to cut about 1/4 end off the end of each and the width is perfect.  I only had to adjust the length so scissors worked fine, but if I had to narrow/cut it lengthwise would use a razor and straight edge of some kind.
- Easy to clean, wipes off with soap/water as the product description states, can't say for long term as only being using a couple weeks.
- Heat "resistant" - noting I'm careful not to set pans on top of the cover, so nothing has melted yet (but I'm not going to test it).  Think this is same silicon as the baking mats, so only takes heat up to a point (obviously easier to control heat in oven than on a stovetop), the cover "sticks" nice so far so haven't had any issues getting too close to a burner.
- Forms a pretty good "seal" on both the stove and counter sides, better on the counter side because the counter does not had a lip like the stove, but the cover sits on top of the stovetop lip ok (the divider on the underside of the cove is off center, which is perfect as I need it narrower on the stove side so it's not too close to the burner).

Cons:
- It's a very matte black.  Wish it were more "glossy" (like the underside) to match my glossy black stove, but a minor complaint, probably hard to do considering the material.
- It was shipped a little bent (probably Amazon), but still straightened out ok after a day or two because it is pliable, if it had been folder in hald hard to say.
- I would not recommend with a gas stove (common sense says that if this handles <450 degrees F (446 per the description) an open flame that's too close or even a really hot pan is a bad idea (natural gas/methane burns at 3,542,  almost 8 times what the silicon will tolerate.

Overall it's the best solution available to the impossible-to-clean-up mess problem, as others have noted the metal options available out there all suck and silicon is really the only option that takes (some) heat and is also pliable/soft enough to seal.  Also appears from other posts the customer service is really good, and they do follow up after your purchase and troll the reviews to make sure you're happy  (I would have posted a good review anyways).  Bottom line I would buy again and recommend to others.