I have three different appliances I burn pellets in...as well as corn as they are all multi-fuel units. All are relatively basic units in my opinion...nothing fancy but they serve us well. In reading the forum and conversing with different members, etc., you hear statements such as how stove "A" must run at high to put out the same amount of heat as stove "B" does on medium with the same pellets, and other similar scenarios. For discussion's sake, I'd like to refer to "efficient" as....uses the least amount of fuel to produce a given amount of heat. Are some stoves just more efficient than others? Specifically, what makes them more efficient? Fan size, pot design, heat exchange design, etc. What are some of the more efficient models on the market today and what are their advantages in terms of efficiency? Perhaps this will be a good discussion to help those that are shopping and those of us who might be seeking an upgrade someday.