Had this for over a year now, replaced the first stage filter twice and the second stage filter once. Hooked this up specifically for our refrigerator water line, as there is no drain nearby for an RO system, and the in-refrigerator water filter ONLY applies to the drinking water system, not the ice maker.Note, our water in the Greater Phoenix Metro area in Arizona is just bad. It has to be treated very heavily, and the amount of minerals in the water could be considered a concern. To the point that I've had to replace the heating elements in our hot water heater twice in 5 years, regardless of annually draining the tank.Water definitely tastes better, and our ice is actually usable. Not completely free of mineral build up, but it is noticeably lesser in the last year. It works, nothing extremely "must have", just good quality. Only downside is the lack of ease to replace the filters.When changing the filters, it must have the OUT port opened in order to release enough pressure to unscrew the filter canister collars. First, always cut off the water supply going IN before doing anything, then disconnect the OUT. Unscrew the collar for the filter(s) being replaced, slowly lift the entire unit from the canister, replace the filter, and set back into the canister and screw back on the collar. Run a few gallons of water through it to pull the air out of the new filter.