Don't be misled by the total weight of the unit, the location of heavy steel plate is important too, not just its total weight.Some unscrupulous manufacturers use heavy plate on the bottom and then very light on the sides and top to reduce cost.The weight of the steel is very important in keeping the unit from warping or being damaged by heavy logs thrown into the firebox. On units with no rust prevention, built-in heavy plate takes longer to corrode. Generally thicker is better.