Product review (4 stars): Good choice for a quick fix.
Obviously, these aren't meant to come in contact with an open flame... but my commercial grade thermador range creates a LOT of heat and has already slightly warped the silicone. I can't complain too much because it was partly due to user error; My husband was boiling water in a 70 qt pot and I think the heat of the pot was too close to the silicone for too long a period of time.  On that note, these do their job as gap protectors and they don't look too bad. This was an impulse buy and I will continue looking for something that is perhaps more durable. This is a great item for the casual cook in search of a quick fix, and the price can't be beat.