I'll piggyback off of this thread since I feel I've got many of the same questions as the OP.
I'm NOT looking to reprogram my car or spend 10 hours a week pouring over data, I want something that I can reliably plug into my 2000 Cougar or my 2000 Durango and figure out what my car has to say.
I've read that many devices don't read manufacturer's proprietary codes, is that a concern with Elm327 devices? I'd think it's simply the device's job to spit out the data and the software's job to do something intelligent with it. Can I get some clarification on this?