Doering's comparison points grew from three to five before the buying decision was finally made. He started with comfort, ballistic protection and cost but soon added customer service and coverage area. Then these categories developed sub-considerations. While comfort is the most important consideration defined by his chief, Level II protection was decided as the minimum need. That led to interesting findings.
Comfort is a function of flexibility and weight.
The concern will be different if you are in southern Georgia or northern Minnesota. Dissipation of heat is more important in the hot and humid climate of Brunswick. Other aspects of comfort, Doering recognized, are flexibility, thickness, and weight. He developed a wallboard where he could chart the technical specifications of various vests and that became an exercise. Not all manufacturers had readily available the information he sought.