There are many choices available when buying a quality water purifier. There isn't only several type of brands on the market today, but also a wide variety of styles available. Choosing the water purifier that fits your needs will depend on several factors.
Water purifiers are not "one size fits all". Depending on your situation, and how your house in configured, you can choose from a counter top model, a style that goes under the sink, and a style that hooks up to the main water supply for the entire house.
Determining the right water purifier for you will have a lot to do with the type of water you have. Municipal water has been heavily treated to remove contaminants, but do have a chlorine and chemical taste. Rural areas rely on water from wells that are dug deep into the ground. While this is natural spring water, there can be a need for purification if the home is near farming or manufacturing plants. Also, this type of water can be heavy in iron and other trace minerals.
Cost also plays a large part in determining which water purifier is right for you. Basic faucet attachments can run about $40 while under counter treatments can run into several hundred dollars. If you are looking into purifying water for the whole house a basement model can run your expense up to $1,000 to $3,000 for high end models.