First off let me say that when I bought my 2005 Mustang GT there in 2005 it was a very good experience. I specifically recommend doing business with Frank Cordova who used to live next to me.
Now for the service department:
The first year there was a well known problem with the fuel gauge and a TSB issued. When I took it in they absolutely refused to apply the TSB and do the repair. It was "Costing them too much money". I went all the way to the regeonal manager with no satisfaction.
A couple of weeks ago I took it in for a problem with the CMCV actuator. I asked for the old part so I could check it out. They did not save the part and would not answer my "E" mails about it. Makes me wonder what they actually did. They also charged me for a "diagnosis, $110. Most places refund the diagnosis if you have the repairs done. I also had informed them of the actual Trouble code and what it meant. Takes about 2 minutes to read the code. That's about $3,000 an hour to do what I already did.