The best reverse osmosis system for the home is the Home Master TMULTRA Ultra, according to Water Softener Central. It also holds a rating of 4.9 stars out of 5 stars on Amazon.com. This water softener costs approximately $459 as of 2015.
With an advanced filtration system and a number of purification stages, the Home Master TMULTRA Ultra system removes 98 percent of chemicals, iron, heavy metals and other contaminants. This is an ideal under-sink system for well water, and it has an ultraviolet filter to destroy microorganisms. The filter is designed to be easy to change and long-lasting, requiring care only about once a year. This unit also has a fast flow rate at almost twice as fast as traditional systems.
A less expensive but still highly reviewed reverse osmosis water filter is the Hydro-Logic 31040 200-GPD Stealth-RO200. This unit is one of the top picks from Water Softener Central and is rated with 4.8 stars out of 5 stars on Amazon.com. It costs about $225.
This system removes 98 percent of contaminants from the water as it moves through four filtering stages, is designed to create very little waste and can process up to 200 gallons each day. There is an ultraviolet filtering system that removes 99.99 percent of microorganisims.