(You should probably place the donut on the rear of your car is front wheel drive, though.)
I read somewhere that you should always replace a back wheel with a donut spare, even if that means swapping a punctured front wheel with an original back wheel. The donut spares are so flimsy that they can't be trusted to reliably handle the side loads a front wheel experiences when your car is turning.
Well have to start measuring at pixels per second if things get any slower