EDIT: Emacs is pretty intelligent when it comes to indenting Python code; it does not merely insert 4 spaces for a TAB, but it automatically aligns your code to the Python expression in your previous line!

I don't know which one is the "right" way, but I certainly prefer Emacs's default behaviour. Maybe I just didn't configure my Vim properly :-)

Example:

    In Emacs:
    def _five(one,two,
    ....,,,,..three,four):


    In Vim, with 4 space Tabs:
    def _five(one,two,
    ....,,,,|hree,four):

    | => cursor position when you press ENTER.