I use the Axe rotary with the Train Wreck amp in front of it for grind. I've been using the Korg G4 for years, but am not familiar with the Neo. The only thing I miss from the G4 is the Stop switch, which spins the Leslie down slowly to a full stop. I like to use a very slow Leslie (.25 Hz) for ambiance, so I don't setup the expression controller to stop the Leslie. With the G4, I could go from any speed to stop by stomping a pedal & the Leslie rotated down in a really nice way. I've been able to re-create all of the other characteristics of the G4 with the Axe.