OK.... I thought I knew what I wanted in a wood furnace until I found this website....now I am thoroughly confused! As I have read these forums I realize that your members have a wealth of knowledge and seem glad to share it with those of us who desire to do things right. I live in North Alabama in a house that is about 25 years old...fairly well insulated by "southern standards". When I started my research on furnaces what I thought I wanted was an OWB to keep the mess out of the house. I currently have a fairly large open fireplace that we use for ambience. It LOVES wood. It will actually get the house warm but is extremely inefficent...I certainly don't have to tell you guys that. We really don't use it to "heat' with. So.. here is where I am currently. Have considered a Portage & Main OWB gasser...seems to be well constructed. The information I'm reading in the posts is that even the gassers in the OWB are not as efficent as the indoor models. So another option I am considering is a Wood Gun and building an outbuilding attached to my detached garage about 60 feet from the house which I currently heat with a heat pump. I want to heat about 3500 sf and DHW. Should I consider storage? What is the difference between "pressurized" and "open" systems? I have 2 -1000gal propane tanks in my "collection" down in the field but feel that even one of them would be too much for our mild winters. Do open systems corrode faster? I read somewhere that the ph had to be just right for a SS water jacket like the Wood Gun? Also read that you shouldn't use too much oak. Oak is about 95% of what I burn... that and a little Black Locust. Thoughts? Other things that shoud be considered in the equation. (from things I've read on posts) Black Oak primary firewood Well water has Iron & Manganese Any advice will be greatly appreciated.