There really isn't a clearcut line between "code reader" and "scanner" anymore. Even cheap $100 scanners have PID monitoring functions now. Many feature bidirectional communication. What really separates the professional $5000 scanners from the $100 consumer models are the scope functions and variety and depth of models and retrievable codes. Buying a $5000 Modis at this point in time is pretty foolish, considering that the trend is now towards PC-based software scanning solutions. In 5 years I think these big handheld scanners will have gone the way of the old dinosaur dedicated oscilloscopes.Yeah, even the top end code readers are not exactly scanners. Scanners can read live PID data and graph sensor outputs, stuff like that. Entry level right now on a basic scanner is still about $300, though over time the code readers will become more advanced.
I use a Dynoscan Palm. Its not as powerful as a Snapon or Genesys, but it can plot live sensor readouts, fuel trims, etc. It cannot read the waveforms on other sensors directly, so for example, I can't see the signal pattern on a crankshaft sensor. Its still much better than most code readers.