We got one two years ago and I am about to have it pulled out. It doesn't work more that it does. Regarding scale buildup.....it order to get it to work at all after 3 months, we had to install a "Reverse Osmosis Filtration System" - about $400 - which is bad enough. Worse is that this system requires two new filters to be replaced every year - and they cost about $300 per year.I've got one we installed about a year ago and we're having a lot of scale buildup. we've changed the water filter 3 times now and have had to clean the sensors and replace the solenoid. it may just be the water quality here but with that many filters you wouldn't think there would be that much scale buildup.