The AEM That we used was the Honda box. Its a great unit but it cant park the Iddle motor as it doesn't have that circuit build in. All JZ engines use a Stepper motor and the Honda box can't control the Main relay like the Toyota ECU does to park it in the right spot. We have now switch to another AEM box that we modify to make full use of all factory like functions. But to answer your question, Yes the AEM unit is better then the EMS 6860.