Most customers believe that the brand of the equipment is the main issue for quality. I agree that it makes some difference, but the number one reason that a system works or does not work well is the install in the home. If that is done right, there are several brands that will do a great job for the customer. I would say it is even 70%+ of the total cause of success or failure.
The top units that several companies make are about the same quality and have similar features and most of the time use the same parts in them. For example, for a furnace the fan system is either number one or number 2 most important to success or failure for the unit to work on heating and cooling the best way. It is what creates airflow. What powers this is the fan motor which is a variable speed dc motor that is very efficient and powerful. These are made by one company so many companies use the same motor for this.
AC units use a compressor made by one company, that is all there is. For this reason the design and install for your needs is much more important than the brand of the equipment for quality, and for performance.