If the supplies cost $20 and you do the oil change its worth it. If they do the oil change for $20 run for the hills. Im a mechanic at a real shop and we have customers coming back all the time after one visit with them. A common one thats been happeneing is customers are told by those places that the drain plug is overtightned and should go back to who did it last and get a refund. Then when they come back to us and we put it on the lift and the drain plug comes out with out a problem we start to scratch our heads. So we gave them a call and it turns out that after a good 30-40 mins on the phone, they finally say that the car was to hot or to close to the exhaust for them to work on and they never said the drain plug was over tightened....This has happened six or seven times this summer alone.