Automaotive scan tools - anybody got a handle on this?

[spray_man]

Tired of paying big dollars for vehicle repairs. I want to be able to diagnose my troubles down to the component/unit/lower level. Some scan tools just give you the top layer of the problem. What scan tool is best? I am getting a lot of input, but not from real end users/mechanics. Does anybody use a PC-based scan tool? My understanding is that you get a better bang for the buck with these units. Is this right?