I was curious if anyone ever owned these ventless, 3,000 btu-8,000 btu, propane heaters? I was wondering if they could be a good emergency heater to heat just one room in the house if power went out? I have a monoxide detector. In the past, I have owned ventless propane and natural gas blue flame heaters and I don't like them because they fumed or filled the house with water vapor. I mean, so much vapor came out, it actually ran down the inside of the windows. Even Buddy heaters fume. Normally, I would be really skeptical about ventless propane heaters, but these have good reviews. But does anyone know about the catylitic pad? How much time before they go bad? I like to keep different types of back-up heat on hand, I wonder if this heater may be a preferable alternative at times to clear kerosene wick heaters.