Well I can tell you the electric/hot plate ones don't work.
I used a 20 gal can, got a hot plate that works and heats up to 300F +, and the temp in my lid thermometer hovers around 150 most of the time. What a waste, but now I know....
So I may turn it into a charcoal smoker instead, but now I wish I just would have boughten a cheap one to see if I like it.
Give us this day our daily bacon.