I go through alot of work boot being a union millwright. In my trade we have to deal with all kinds of different elements and chemicals depending the places we are at. I have to say from the start I had no break in period, just comfort from the begging. Had them now about 6 months and still comfy and holding up well. Through the heat, rain or snow the boots have been great. Heavy enough but not too light and durable. Damn great pair of boots.