I'm updating the review below as they did show up around 6:30 and fixed the issue without a charge. While there is no excuse for the lack of communication they were apologetic and professional when they did arrive.
The absolute worst customer service I have ever experienced. Had an appointment this morning for service between 7-9. 9:45 rolls around and nothing. Call the office and am told it's been moved to between noon - 1. 2 o'clock rolls around... nothing. Again, I have to make the call. They're running a little late and will give you a call when they're on their way. 5 o'clock now... nothing. Sensing a pattern? Called, but the messenger service picked up. Told them to relay the message that I never want to hear from these people again.