I have a 03 YZ250f and my ride buddy also has a 03 YZ250f and just got a Vortex X10. We went for a 70 mile ride Sunday and traded off. He has a CRD pipe and I have a stocker with a pro-moto end cap. First off let me tell you that mine seems to be a little more snappy and seems to rev quicker. I believe this is due to the stoke pipe being about 3-4 inches shorter than the CRD. The CRD is nice and is quiet and makes good power it just doesn't seem to come on quite as quick. Mine also has about 300 mile more than his and may be a little looser :>) Anyway on to the Vortex... it does solve the miss everyone is having at 1/2 - 3/4 throttle. It also seemed to make his bike smoother??? We tried some of the settings and I always found that the non adjustable position was the best. The traction setting really did seem to work well and make it softer and more controllable roll on which was nice on the huge hill climes we were doing that were slick. Overall I would have to say it did make the bike run better, start better, and possibly make more power. I have heard people say 3-4 HP and I have to say no way. That is a bunch and you would really feel it. Will I be getting one??? I don't think so, it is a nice product and works well but I am really happy with how mine runs stock and love the big mid range hit it has. I am spending money on the suspension and other goodies. Would I recommend it? Sure, it works well and does what it is advertised to do.