I think it depends on the vehicle being discussed. If it's a smaller sedan then a 4 cylinder is usually more than adequate for commuting purposes. SUV's suffer at high speeds due to their wind resistance and 4 cylinders need to work harder to overcome this. Working hard equals loud interior.
If the option existed I would stick with whichever engine offers the best gas mileage, although the difference would have to be at leat 4mpg to make it worth getting a 4 cylinder for the additional noise it creates. Again this will definitely depend on the vehicle being discussed.
Now if you like to have fun during your commute an 8 will certainly spice things up.
