Traditionally people bought trees inside during midwinter festivals to keep the spirits of the forests comfortable and warm. To assist this, they decorated the trees with food and goodies as well as symbols to show the spirits that they were friendly and welcoming.
Therefor I like the idea of a real tree. I understand a faux tree will be easier and they're good to have as a back up in case one year you can't afford or have time to get a real tree, but I find real trees are easier to put up and discard after the season.
One thing a faux tree can't give you is that scent.
But I mean to be honest, I don't really care either way.