Well. Consumer Reports is a very good organization sends out an annual survey to its subscribers asking for reasonably detailed information about their experience with home appliances, vehicles, etc. They then report the results of the survey in a future issue.
Problem is, replying to all or any of the survey is optional. That means CR is more likely to hear from two types of respondent: those who've had trouble with a device (satisfied customers usually don't bother); and the types who take meticulous care of their possessions, and like to note and brag about how those items perform.
Unhappy customers will weight the responses against a particular model or brand. The meticulous types will weight the responses in favor of the model and brands they've taken good care of.
See where the bias in each case can factor in? Lemons (happens to every model) will get disproportionately reported, and a lot of the bias behind the high-performing models is that they've been owned by people who performed the necessary maintenance and were proud to report on how well the device held up.
That's the most common criticism of CR's owner survey reports that put foreign cars ahead of domestic vehicles. The argument is that originally, foreign car owners were the types willing to purchase a vehicle that would require them to get more involved in the maintenance since local shops weren't familiar with them. The owners were proud of maintaining the vehicles and were happy to report how well they performed. Then the selection bias kicked in: people began hearing that foreign cars were better, so more people began buying them. Those who bought them were more likely to maintain them, and so the bias continued.
In that respect the car brand debate mirrors the a/c brand debate: some brands have superior or inferior characteristics, but a lot of how well and how long the product will perform depends on how the end user maintains it. And in the case of a/c, how the installer selects and installs it. That, by the way, is Consumer Report's main point: the brand plays some role, but they do say the primary factor is choosing the right hvac contractor.
Also, ConsumerSearch, a consumer-oriented website unrelated to CR, says this about a/c brands:
"We found more criticism and complaints about Goodman (makers of the Goodman, Janitrol and Amana brands) than any other brand. In spite of that, most contractors maintain that the problem is not with Goodman products, which are sometimes less expensive, but with faulty installation. These pros say that other manufacturers, such as Trane and Bryant, establish stringent requirements for technicians who install their equipment, while Goodman will let anyone install one of their air conditioners. When these pros repair Goodman units, they often find that the problem is not defective or short-lived parts. If you buy a Goodman air conditioner from a skilled contractor, they say it will be as reliable as any other brand."
HellT