I'd say you would notice it if you had it - mine was horrible. I grinned ear to ear when I fire fired mine up after the install and heard that idle note. Once I got on the road and set the cruise it turned into a frown. When I got on it and let off and the "cackle" started - I turned around and went home and ordered the resonated version. That is what I should have done in the first place. Tried to save a few bucks and wound up having to buy both. Resold my test pipes, but ate some on them. Resonators fixed mine 95%