Rated average almost across the board because of these reasons. I use the bike for Motocross only for anyone that needs the know to relate to what kind of riding they do. First, it doesn't fit properly, likely because it is spec for pre 2005 all the way to current model year, 2005 started the alum frame, it is thicker than the steel frame YZ so it hits the frame rail, I had to make it fit so it didn't hit and vibrate. Second after I jetted it the power is great in the mid range comes on strong, off the bottom is not as good as the stock pipe, the top may have a little more pull than stock. Basically it looks sweet, unfortunately it should fit right without tweeking it and I wouldn't say it it is more broad across the board as advertised, so its average.