I've been taking my car to Griffin for 4 years now, and he's always provided great service and deep expertise on some complex problems. The owner has always allowed me to wait for my car, all the while working through their wireless network. I've purchased some expensive Recaro seats, numerous performance upgrades, and even some 4 point harnesses to be used on the track. In all cases, Griffin did what they promised, and on any occaision where something was not done to my satisfaction, they always reviewed the work with me, and made whatever corrections were necessary. I would love to think that diagnosing a car properly was something that a mechanic could guarantee for you, but the dilema that they face is that often times, in order to be 100% sure that they fixed the problem, they need to spend extra time driving the car, or running additional tests. So, if you accept that it's not possible to get it right every time, then I think you'll agree that it's most important to use a shop filled with qualified mechanics, but to also have an owner that is reasonable, and wants his customers to be satisfied. I trust them to do work for me, and will continue to do so.