Glad I am not the only one not to trust garages.
Putting my car in for the £99 oil/filter & mot @ JCT.
Told me they would use the oil that is recommend for the car. Want them to use the castrol edge long life, which they confirmed they would if the car is on long life service. 4.6l of that stuff with the filter doesn't leave much profit.
So I bet they only use bog standard oil & filter is universal. Told me I would also need the spark plugs air and pollen filter if they were not done at last service @ £115 total. Lucily they were, but I think last garage used standard castrol semi synth oil.