My husband and I have been using Comfort Shield Heating and Air Conditioning for only 6 months but so far they are doing a great job. Our air conditioning unit stopped working recently so we called them up. It is always easy to make an appointment and get them to come out by the next day. I am not sure what was wrong with the unit as my husband talked to the technician but I am happy to say that it is now working. The technician was professional and knowledgeable. I recommend them!