I think that when your car is under warranty it is to your advatage to have an A or B service. Often times the techs will find problems that will be covered under warranty. The MB tech knows exactly what "problem areas" to look for on each car. Does Jiffy Lube look for warranty work to be done on your car, do they look for loose ball joints, tie rods, leaks, brakes, test drive your car, check the drive shaft? Does jiffy lube put the right oil in your car, the correct amount, the correct filter? Is it worth blowing the engine on a $60,000 car because you saved a few dollars on an oil change.