I bought this because I needed a fair amount of distilled water and really did not want to pay over $3/gallon and lug all those jugs home from the store and to the recycle center.
The distiller works very well. If all you are planning to do is distill water, simply attach the handle to the pitcher (this is a little tricky--you will need a non-included Philips screwdriver), The distiller seems to be pre-set for the time and temperature you would need for water. Some people use it of other distilling. For this, you would need to know more.
The first time you use the machine, there is a cleaning procedure which involves putting a little citric acid powder and a little water in the main unit, setting the fan/heating part on top, plugging it in to the main unit, plugging the main unit into the wall plug, and hitting the "start" button. This cleaning is done at intervals (a month?) therafter. All this is in the instructions, but you have to hunt for it!
The instructions could be better written and organized.
After the set amount of time (1/2 hour, if memory serves me), turn it off, let it cool down, empty the water out of the pitcher and the main unit, rinse the pitcher and wipe the main unit (you don't want citric acid if what you wanted was pure water), fill the main unit with a gallon of water, put the fan/heater on top, plug everything in, align the pitcher to catch the water, and in 3.5 hours you will have a gallon of distilled water. There are a few charcoal packets included if you wish to use one as part of the process (it wedges into the spout that empties into the pitcher).
The fan makes significant fan noise, and the heater part does raise the ambient temperature in a small room several degrees. The unit is well insulated though. The walls and counters it is near or sitting on do not heat up. Keep anything flammable away, particularly from the top, of course. Be careful in handling the fan/heater unit. It is probably best to wait until it cools off.
This little machine really does work very well. I splurged and bought the red distiller, and it is very beautiful. I can see how much stuff is removed from the tap water by seeing the minerals remaining at the end of the cycle! Our water here is fairly soft, and even so, there is a lot that gets removed! I am very pleased with this purchase.