Absolutely excellent! I received a call from my tenants. The AC had suddenly stopped working, and (of course) it's that time of year in AZ when 100 degrees is the norm. I contacted AZ Dukes of Air as soon as they opened in the morning and they arrived within 1 1/2 hours. In fact, they called to say they could make it earlier then our scheduled appointment time. They evaluated the problem and determined the thermostat was broken. They supplied the new thermostat and did a service check of the AC unit; cool air was circulating again within an hour of the Dukes arriving onsite. All of this was done for less than $150. Amazing!! I wish I had met them sooner. Thank you AZ Dukes of Air. You were a lifesaver.