Somehow it looks easier and clearer to use TAB over Spaces.
Now that you linked me PEP8 (First time i see it) i will start using 4 spaces.
Thanks for your comment
You're welcome. There's a pep8 package on PyPI that implements validation against that recommandation and plugins for most popular editors that make it easy to check your code. Editors can also be configured so that pressing the tab key actually inserts 4 spaces.