I prefer an awareness that the hand can administer a hug or a smack, and the child's behaviour will determine which is dispensed. A "rod" is over the top in my book.
Well, the purpose of spanking is to make a stinging sensation that creates a connection between inappropriate behavior and negative consequences. If I were to use the palm of my hand, I would not be able to deliver that stinging sensation unless I hit the child really hard. A sting can be applied without hitting very hard at all. Just a flick of the wrist.
The special punishment "tool" is a bit too Taliban for me as well.