I would have rated this a 5 except for the fact that twice now my windshield washer has not been filled although it was ticked off. The second time was the day after the service it was a snowing and roads were slushy - I had only a small amount of washer fluid and had to pull over to clean my window, fortunately I had an extra bottle in the trunk. If this had only happened once I would have dismissed it as an oversight but the second time was a little frightening. Other than the foregoing I have only had good things to say about OMS.