We've now had this distiller for about three weeks, and used it for probably two gallons (cycles) a day average. Mostly the water is used for humidifiers, but also for the Aerogarden, etc. We do NOT use it for consumption, even in the espresso machine where we use distilled water due to scale. (We're in a very hard-water area.)It takes several hours, with a gentle fan whoosh, to produce a gallon. You can tell it's removing a lot, because a lot of crud gets left behind. It forms a white crust on the bottom, and smells funky. The distiller came with a citric acid powder that makes cleaning it really easy.I did buy the extended warranty from Amazon, based on several reviews saying their unit broke.The reason for four, rather than five, stars is that the water doesn't taste as good as commercially distilled water. My guess is there are two reasons for this.1. This distiller, which is very inexpensive, does not have a vent for VOCs. So anything that evaporates at a lower temperature than water (think benzine, alcohol, gasoline - although mostly stuff you'd find in water, those are just examples) will ALSO land in your distilled water. A more sophisticated design would separate those from the water.2. The unit knows it's done by the temperature. In other words, when it gets above boiling temperature, it shuts off. Which works, but will also evaporate anything that has a boiling point just ABOVE that of water, again sending contaminants into your water. e.g. naptha, toulene.Neither of these makes this unsafe - it's not ADDING contaminants. And, looking at the offerings on Amazon, pretty much any reasonably-priced distiller has these same flaws. But, as this is my first distiller, the taste disappointed me and I tried to figure out why. Hence the four stars.So, bottom line: It's easy to use and effective at removing a ton of crud, but it's not perfect. But you'd have to spend at least three times as much to get better.