My husband and I purchased a home last year and the first thing that we did was look into changing the water softener. We went to Sears where they took a sample of our water and tested it for hardness and also acidity. We watched the test right there. Then they discussed our needs and went over which softeners do what, how much they cost, installation, etc. We purchased one during one of Sears 10% off Saturdays. Since it's Veteran's Day, they may have that 10% Saturday tomorrow.
The installation was performed by a licensed plumber and a technician came by a few weeks later to make sure that the machine was working properly and that the installation was correct. We have no problems and no hard water. Very pleased with their service and attention to our needs. No hard sell from the salesperson, either. Just my opinion.