The Waterdrop unit is well designed and engineered. Designed in such a way that it is very easy to maintain. I have owned many tank-type reverse osmosis systems in the past, but this unit is by far better than the ones I have previously had. I had read many of the negative reviews on the unit and most of them were because of the water quality coming into the unit. The unit has no control over the water that it is being fed. I already know I have poor water quality so to eliminate this being an issue I added a 10-inch 10 µm filter as a pre-filter to the Waterdrop unit. By doing this it will ultimately protect the three filters inside of the Waterdrop unit and will ultimately extend their life. (10" Housing and filters readily found on Amazon) This resulted in a very clean installation. I worked for 43 years in the facilities department for a large medical company which had multiple reverse osmosis systems. This seems to be the best point of use unit that I was able to find. It is a little more expensive than tank type units, but you get what you pay for. Well worth the money.