Product review (5 stars): Works as advertised.  Stays in place.  Feels like great quality.
It has stayed up between my counter and stove quite well, too well in fact.  It can be a little tough to work the gap cover in to the gap depending on the size of the gap.  In fact, i could not fit both of them on both sides of my stove.  If you have smaller gaps (less than 1 inch) it will be tough to get the gap cover in there.  I moved the stove all the way to one side and am only using one of these covers.  Despite this, the cover works perfectly as advertised.  It is made of a thick, durable feeling silicone/rubber material.  It stays in place and does what it is intended for.