I've used Dobbs many times for oil changes, tires and misc. repairs. They do pretty good work so quality really isn't the question. However, I have noticed that when my wife takes in the car, they sometimes add a few repairs that don't seem to be necessary and the estimates don't always reflect the final price.
I don't think these guys are deliberately trying to cheat anyone but I would keep an eye on them if they suggest additional repairs. But I've never had a problem with their oil changes or routine maintenance.
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