Be prepared for more quirks in jetting. I agree with pat in having been down both roads I think the modified air box works just about as well. I does make rejetting easier. And the 160 supplied jets do not neccessarily work for everyone. I'v had more success running uni pods on mine. And I think performance is effected more by changes in temp and elevation than with the stock air box. But on a good day you can make more power. My fuel mileage was mostly uneffected by the change. Still between 45 and 50 mpg depending on my behavior.
