I never trust the mechanics at a dealer. I always take my car to Whitey's whenever the smallest thing happens. They are very helpful, and they give me couple of choices.
I first met them when I got a $1200 quote to get my ac fixed when I was in college from a dealer. My friend referred me to Whiteys, and they fixed it for $180 and some change. It ran cold for 3 years when I sold the car.