When evaluating igniters, prioritize material composition and thermal resistance. For Hot Surface Igniters (HSI), ensure the use of Silicon Nitride (Si3N4) over Silicon Carbide if high durability and faster ignition times are required. For spark igniters, verify the ceramic insulation grade (typically high-alumina ceramic) to prevent voltage leakage. Key parameters include operating voltage (120V/240V), wattage range, and minimum temperature rating (typically >1200°C) to ensure reliable gas ignition.