I have been using Bob and Degree AC for several years and have found them to be reliable and excellent at their work.
They originally corrected a faulty installation of a new unit installed by another contractor and since that time they have been performing service every six months under a contract. If I don't call them, they call me. If they make an appointment and there is a problem they call you to keep you appraised of their schedule - not like most service contractors who hang you up.
They have just completed a duct sealing of my entire system They were clean and efficient and it has resulted in stopping almost 20% of my conditioned air from escaping into the ceilings.
These are good people.