I used to run a Surdiac also and I liked it very much. My heat exchanger never rusted out but my hopper cracked and split. A new hopper cost me about $400 around 10 years ago and it was well worth it. That stove burned about 2 tons to keep my house warm from November to April every year and saved me a bundle in heating costs. By the way, there was a Surdiac dealer in Kutztown, PA about 20 miles from where I used to live.