Do you think big or small towns are better to raise a family in?

My and my girlfriend were having this debate recently, I grew up in the middle of Toronto and she lived in a town of 12,000 people. I love big cities! I think growing up in a big city made me more open to other ideas and people and would love that for our (non-existing) family. She says once we have kids she wants to move to a city that's quite and everyone knows each other where you don't have to worry about your kids when their out. This is just hypothetical because we are both still in university and don't have a family yet. Thoughts?