Since all softeners work on the same principal, the big variables are size and price. Some installers will repipe the hose faucets so they do not use the soft water. Others will just pipe soft water to the water heater to make an easy connection. If you are concerned about a low sodium diet, then you do not want to drink sodium softened water. But, a filter will not remove the sodium. You either need an RO unit or bottled water, if this is a concern.: I need to purchase/install a water softening system, i live in a very hard water area.: i have priced out models at the store and compared to some companies services, they are about 1/2 the cost, w/ the same features.: is there really that big of a difference between these units? i mean, ignoring the installation, is it really worth 2x as much to have a supplier install the system vs. purchasing at the store?: i realize there are features to consider, but I am not seeing a huge difference in capacity/features.: also, using the sodium softeners, is it really necessary to filter drinking water?: any help is appreciated.: crystal