Their installers mistakenly wired our air handler such that the auxiliary heat strips were always on. So the chilled air was being heated by these strips as it was sent into the house. After several service calls, they discovered the problem and re-wired it the right way. The rooms were cool, the system only ran periodically and my electric bills went down.
Pros: they finally fixed my problem
Cons: they didn't reimburse for damages caused by their installation errors