We have been through Phiily twice with an hour and a half layover. Both times we had to transfer between terminal A and F. The first time we had checked luggage and barely made our connection home and wouldn't have if not for a helpful Manager/gate agent. The second time we had carry on luggage only and had plenty of time. I actually liked Charlotte better as we didn't have to change terminals there. We also have Global Entry now which speeds thing up.