I would suspect you'll see more vibration period although it will be greater is certain rpm bands. I would also say that just becuase your not feeling the vibration doesn't mean it isn't there. I would like somone to give mil's of displacment at the crank before and after but I would think there would be a noticable difference. This would mean you'll have premature bearing wear. How much? who knows without testing. Will it reduce bearing life from 600000 miles to 400000 miles? Noone knows.