The cooling system is critical for the machine's lifespan and patient safety. Prioritize suppliers that use a triple cooling system: Water, Air, and Semiconductor cooling. Ask for the water pump specifications and ensure there is an automatic alarm system for low water levels or high temperatures. Regarding longevity, inquire about the lamp life expectancy, which should ideally be between 500,000 to 1,000,000 shots before requiring replacement. Requesting a video of the internal structure can help verify the quality of the components used.