Before I get anyone all fired up I am under the belief that the surface you run on play a huge role in what pipe your going to prefer.........High bite surfaces and slick surfaces are radically different loads to our engines....And how a 2 stroke engine reacts and throttles is very dependent on the load load placed upon the engine.....Different pipes and headers will react differently depending on the load working against the engine...so what is ideal on slippery tracks may not be ideal on high bite tracks and visa versa....Also to factor into it is the reactivity of the fuel being used...some fuels are naturally extremely crispy and other fuels are much less crispy........Some will look towards using a bottom end pipe and long manifold to overcome the laziness of a high oil fuel or low nitro fuel........whereas with a reactive fuel we can run more top end oriented setups and still have all the crispy low end throttle response we can handle........