Product review (4 stars): Works well
I have bought several of these in the last few years.  They work fine for my gas stove.  My only concern is that over time the metal starts flaking on the bottom side.  I have not had to wash mine - they just live on my stove top permanently, so I know it's not rust on the bottom even though it looks like it.  I don't care for having to clean up the flaked pieces, but for the price of the diffuser - I can't expect much more from it.  Lose the leather tie on it - not sure of it's purpose except to come close to starting a fire on your stove top if it gets to close the flame.