Heavy-duty mixers vary in size, wattage, bowl size, and cost. Wattage varies from 235 watts to 1400 watts. In order to make 8 pounds of dough, which makes 4 large loaves of bread, a 6-quart bowl and at least 600 watts of power are needed. A 325 watt machine will handle it for a time but will eventually burn out.
     When buying a machine, consider how much bread you will make and how often you will make it. Also consider the bowl size, how easily ingredients can be added to the bowl, and ease of clean-up.
     Most mixers of bread kneading capability also have other attachments. Sometimes, which attachments are available and their quality can help make a decision.