Product review (3 stars): Works well
Stovetop extender did what we wanted it to.  The sides are not quite long enough for the magnets to touch the magnetic parts on our stove/range, but the gap is small enough that the extenders fit well and serve their purpose.  You will need to remove these every so often to clean some dust that does get through .. but having them in place is much better than not..  I would recommend them... though $18 did seem a little pricey.