The latest batch of models posted to our refrigerator Ratings includes the $1,100 Whirlpool WRT771REY, a top-freezer that combines excellent energy efficiency with very good temperature performance to earn a spot on our recommended list. What really sets this Whirlpool apart, however, is its through-the-door water dispenser with built-in filtration. While this feature is common with bottom-freezers and side-by-sides, no other top-freezer in our Ratings offers it. But then, very few top-freezers cost more than $1,000, and some top picks sell for between $700 and $800. So is it worth paying more for water?

It depends, of course, on whether your home requires filtered drinking water. Some people prefer the taste of filtered water to tap water, while others consider it a safety imperative given the potential presence of contaminants in their water supply, such as lead and benzene. If you do require filtered water, having it come out your refrigerator dispenser is a nice convenience. However, in the past we have found some refrigerator filters to be so-so at removing impurities (we have not tested the filter on any new refrigerators, including the Whirlpool WRT771REY). And so, if you're concerned about the presence of serious contaminants in your home's water, like arsenic for example, you might want to consider a more robust filtration system, such as reverse-osmosis.

Another caveat with refrigerator filters is that the replacement cartridges can be pricey. The Whirlpool user manual says the filter should be replaced every six months and the suggested retail price on the replacement filter is $50. By comparison, the estimated filter cost per year on top-rated faucet-mounted models in our water filter Ratings is between $20 and $45. Then again, you could spend $200 or more on replacement filters for some countertop and undersink systems.

Bottom line: a refrigerator water dispenser can be a convenient feature, but you might be able to get cleaner water for less by choosing a dedicated water filtration system for your home. See our Water Filters buying guide for more information.