Product review (3 stars): Questionable purchase - Does it really work?
not sure about this brand as it never had that PoP when the new cartridge got installed and I didn't get the dark colored water initially as in the past fro the Home Depot brand which you are instructed to keep running the water for 4 gallons or so until it rinses clean.  Right from the start it was clear so not sure if even working right?  Will not buy again.