Define the purpose
What softening is intended to address
Water hardness is associated with dissolved minerals, principally calcium and magnesium. A softener addresses those hardness minerals. That purpose is different from choosing a filter for a particular taste concern or a reverse osmosis system for a drinking-water point.
Keep the goal specific when comparing equipment. Discuss the deposits or cleaning issues you want to address, while asking which benefits the proposed model is designed to provide. Softening should not be presented as a universal answer to every water-quality concern or an explanation for every plumbing repair.
