Came across this very informative article: http://www.hearthandhome.com/James Houck Articles/HH_11_February.Catalytic Comeback.pdf Some very interesteresting quotes, some surprising, some already common knowledge: "On average, catalytic heaters have lower particulate emissions than non-catalytic heaters" "most modern certified non-catalytic stoves have smaller fireboxes because it is more difficult to reduce particulate emissions low enough to be EPA certified if the firebox becomes too large... This is not the issue with catalytic technology; these are heaters with larger fireboxes that can be certified more easily." "What is not just a marketing claim, and generally accepted, is that, as a group, catalytic wood heaters are more efficient than non-catalytic wood heaters." "well-designed, modern catalytic wood stoves "protect" the catalyst from thermal stress and direct flame impingement, and... tests suggest that catalyst degradation in a well-designed stove is not an issue." (I personally have some doubts on this particular claim.) "the mean emission factors for catalytic stoves were much lower than for non-catalytic stoves at the lower burn-rate categories, suggesting a disproportionately better performance of catalytic stoves than non-catalytic stoves at lower burn rates."