Is it a powerfull tool? Can you reset servicelamps etc with it?
I don't know about "powerful" but it can read codes, reset the check engine light, synchronize TPS and Idle speed control, show volts, RPM and a buncha other stuff. The big convenient thing is removing codes and turning that check engine off conveniently.
Is it worth 200 USD or whatever they want these days? Probably not. You can do nearly everything without it.