As of 2015, the top water softeners are WaterBoss 220, Fleck 5600SXT and the Nuvo H2O Manor, according to The Water Softener Critic. Amazon.com gives them 4.4, 4.6 and 3.7 out of 5 stars, respectively, and reviewers at the Water Softener Center give them favorable ratings as well.
The WaterBoss 220 is a 22,000-grain capacity system that is compact, efficient and can soften up to 70 grains per gallon. The softener has a turbo regeneration time of 18 minutes and an internal self-cleaning filter. The Fleck 5600SXT is a 48,000-grain capacity system with digital controls that automate the regeneration process once it is set. The Nuvo H2O Manor is a salt-free 60,000-grain capacity system that uses nanotechnology to soften water and is eco-friendly.