I just picked mine up today!
Having used both Equus and the Sears models before, this is money well spent on the AE. You'll get a ton of usefull data that a typical code reader just doesn't read. I like its ability to record specific bahaviors that can be shared with others (helps, when you need expert advise). Anything they don't cover, I'm sure you could submit a request for...
Also, take a look at this.
SpeedTracer Stage I