Buyers should choose based on the Risk Level (Class 1, 2, or 3). Class 2 vests are the most common for security personnel, offering a balance between cost and safety for traffic speeds under 50 mph. Class 3 vests, which include sleeves and more reflective surface area, are more expensive but mandatory for high-speed environments. For specialized security, FR (Flame Resistant) treatments or anti-static properties can increase the unit price by 30-50%, so it is vital to match the specification strictly to the end-use scenario to avoid over-paying for unnecessary features.