On one of my rental properties, my tenant convinced me to get it. I got the service contract from njng that covers the HVAC and water heaters, for about 40 a month. They added freon twice, and replaced a bunch of parts in my water heater. They do not cover whole replacements still not sure if it was worth it, but if you have an older system that are prone to breaking down but is generally fixable it would probably be worthwhile