This company botched ever aspect of our installation.
They didn't taper the ductwork as was the plan. Drilled duct holes out of alignment. Hung supports out of line. Didn't pitch the unit properly, resulting in an extreme amount of water raining into our dining room, and water travelling along the length of the duct and dripping into the kitchen.
Little things too, like how they installed the thermastat, that it was programmed to fahrenheit, the sloppy holes drilled into our walls and ceilings, and the extra holes they drilled because the first were in the wrong spots.
Fixes were late and forced. Scheduling in general was always a challenge, resulting in much of the installation being done without owner being on site (and needing to be redone). Traps for the drain lines were installed poorly and reluctantly after much debate on their merit.
I can't believe the fiasco this has become. It is comical how hard it is for these guys to do the simplest things. After this installation I'm sure I know more about AC installation than they do. At one point they tried to tell me there wasn't negative pressure inside the unit because they didn't want to justify the lengths of their drain traps. They needed constant supervision, and at times we were teaching them how to do their jobs correctly (how to put things in a straight line).