Tell you mate to just stick with the SAFC, does the same job really. If the ecu is picking up knock it will retard timing. The knock sensor does give you something to look at when your sitting at the lights, watching it slowly creep, nowhere near dangerous however... but thats about all it does for me.
That is ofcourse if the warfies and sneaky boat people dont steal the safc outa the car on its way over from japan...