OBD2/Diagnostic scanner...Matco or Snap On???

I've used the Genysis, the Modus, the Solus, as well as a few manufacturer specific ones like the IDS, the WDS, the HyScan, the GDS, and the DRB. Right now I have the $135 Harbor Freight special. It does the basics well. I can graph 02's, read misfires, read short and long fuel trims, and a few other PIDs, as well as freeze frame and pull live data. I can even pull manufacturers specific codes. It was half the price of the same version my buddy bought from MAC and does twice as much. I will say, though, that one of these days it'll be relegated to the bottom draw in place of something with more capabilities as the money allows, such as the Genysis or the Solus. But that's in the future as the shop becomes more profitable.

Just as importantly, I think, is having a good diagnostic software available to you, one with flow charts, electrical diagrams, etc. I spend more time sitting at the computer pulling up flow charts and diagrams than with the scanner in my hand after I've gotten the codes and read the PIDs. With all the scan tool capabilities at my fingertips at the dealerships I was the same way there. Spend money on a good DMM, too.