I have always put new tyres on the back. In addition to the argument that I prefer to brake less efficiently than lose the back, I have always found fitting new tyres to the front non-sensical; in a FWD car, they will always wear faster than the ones at the back, so any braking benefit is short-lived.
Plus, I never keep tyres on that are over 4-4.5 years from their manufacture week, back or front. I lived to tell the tale, but I was on a DS and odds were then in my favour.
Kostas