I used Larson Air-Air Conditioning and Heating Service to install an air-conditioning system in our home awhile back. They got the job done and our air-conditioning works well. We did have an issue at first with the installation, however. The guy who came did not install it correctly, and he had to come back a couple of times after the first time to properly install it. Obviously the guy didn't know what he was doing at first. But it works great now after he installed it the last time and I haven't had any problems with it.
They still do annual check-ups on our air-conditioning system, and just recently they came to check. They came promptly and gave good customer service.