I got two of these for a crested gecko vivarium and I've had them for about 6 months. One is still in use and doesn't seem to show any signs of breaking down or that it's molding. The other I did end up tossing after finding some mold on it. I didn't want to chance anything since I just had to redo the vivarium due to an issue that cropped up. All together I still think this is a nice investment and that if I hadnt had the issue I did both would still be in the enclosure. I will definitely get another when the time comes that it needs replacing.