hi there i have booked my car in for a service at my local independant vw audi garage for a 56,000 mile service my question is at the last service the oil that they used was the quantum 5w 40 .is it worth putting moble 1 in with the mileage on the car and also will this quality of oil be ok ,,,and also what kind of oil are you guys using ,,,,,,,,,,thanks