Why not moleskin?
It's too thick and like most all other adhesive products, it just doesn't stay put. Before long it's wedged between your toes causing more trouble then good.
Not only do you have to break in the boots, you have to break in your feet. Toughen up your feet by walking a lot and you'll have little or no trouble with blisters. In the mean time, your probably going to get blisters and the best way to treat them IMOHO is with a liquid bandage such as "New Skin" since it does not have the problems Moleskin and other bandages have. I.E., thier too thick and don't stay in place.