First off you do NOT need the performance switch leather knob to enable your performance shift. If you read my write, I said in there you do not need the shift knob to activate it. You need simply a flip switch to activate and deactivate the PS mode. You just need to have the wiring setup for the PCM to switch it on and off. And you can have a grounded flip switch on the dash or center console if you want to do the same thing as the leather shift knob would do.
Its really just a preference to keep my car looking as close to stock as possible inside.