A furnace is not a stand alone appliance, like a refrigerator or washing machine, which can be operated and tested in a laboratory setting. You cannot simply plug a furnace into an electrical outlet and record how it operates. A furnace is part of a system, and it is that system, right or wrong, which will determine how well the furnace will run and also how long it will last.
Famous name brands are meaningless if the installer does not know what he or she is doing. The manufacturers can advertise on television all they want, but their product’s function depends on the installer, not the name brand. Granted, some furnaces are better than others, but the best furnace in the worst installation is not better than the worst furnace in the best installation. A furnace needs proper ducting and venting and tuning to work properly, it cannot work well on its own.
Consumer guides cannot compare furnaces because each installation must also be compared, and this is impossible. The AFUE or efficiency may be compared, the height and weight and costs may be compared, but how well the furnace works is completely dependent on the installation.
Choosing a furnace is not the homeowner’s concern, it is the contractor’s concern. Choosing a contractor is the homeowner’s job. Choose an honest reputable contractor, and most likely, his experience has taught him which furnaces to use and which ones to avoid.