Only been using it for two days but this thing is a work horse and to all the people who say the heater doesn_ work they are full of sh_ this heater has the water steaming right now it seems like it only kicks on when the unit is on and cleaning though.This thing crushes the ability of the HF ultrasonic cleaner that thing didn_ do half as good of a job as this.I can_ speak on the longevity of the product yet but I_ sure it will last a while plus I usually take 10-15 min breaks after about 20 min of use to let the transducers cool down that usually helps extend the life of the unit for quite a while had to learn that lesson the hard way.Also make sure you fill the water level to the line at the top they aren_ designed to be run half full or even 3/4 full.Unit holds exactly 6 gallons of water in the tank.