Product review (3 stars): Be sure to measure from the tip of the counter to where the rubber will meet the back of the stove - Do NOT measure to the wall
We have quite a gap between our stove and the counter, plus the stove is quite a bit higher, so I think I really needed some with taller "T" inserts (the part that goes in the crack to hold the gap covers down).  They slide around a little.  Otherwise, they do the job.

Also, BE SURE when you measure your counter to measure from the outer part of the back of the stove and NOT measure from the wall.  I couldn't figure out why I couldn't find any of these types of gap covers long enough for the width of my counter.  All the ones listed on Amazon were all a few inches short.  I forgot that with the T insert that goes into the crack, there's no way it can reach all the way back to the wall.  So these are actually slightly too long for my counter top.  If you get a size that's a better fit, they may work better for you.  :)