As of 2015, customers can read reviews of Holmes brand humidifiers at websites such as TopTenReviews and Airbetter.org. They can also be found on the JBP Reviews website and on Amazon.com.
TopTenReviews offers reviews for specific Holmes humidifiers and mentions how they rate against other top performing humidifiers. If a particular humidifier is scored high enough to be in the list of the top 10 best humidifiers, then customers can compare the units side by side to get a better idea as to where an individual humidifier stands.
Airbetter.org and JBP Reviews offer comprehensive reviews of many of the popular humidifiers in the Holmes line, including ultrasound, warm mist and cool mist humidifiers. JBP Reviews states the overall positive and negative points about the Holmes brand. The website also goes into greater detail with several other models. Airbetter.org has a similar format. However, it reviews more humidifiers than does JBP Reviews and also goes into detail about filter choices.
Reviews on Amazon.com don't come from actual product testers, but from customers that own the product. The amount of reviews received by a specific Holmes humidifier can vary greatly, but potential customers can use these user reviews to spot common problems and make purchase decisions.