I have a m3 that was due for a inspection 2 service, and check engine light was on. I called a few shops around the valley, and felt comfortable with Christopher at CSmotorwerks. When I arrived I was a little skeptical. It is a small one man shop operation, but Christopher seemed really knowledgeable about BMWs. He has about 30 BMW certifications from BMW so I figured I would be safe. He had the car done the next afternoon, I was shocked at how fast he performed the service. Well I payed him 800 dollars for the inspection, and I truly felt a huge improvement. Engine runs so smooth, engine no longer ticks, and acceleration seems to be restored. I'm a happy camper. Will definitely be back.